Will phone cameras ever be as good as a (D)SLR or mirrorless?

I sometimes find myself in conversations about DSLR cameras and phone cameras.  It usually happens right after Apple launches its newer and better phone unit every year.  We can save the topic of why Apple's newer units are always better than the older ones for another day.  So anyway, someone always says to me that their new Apple is better than my (insert camera name here) that I have invested/sunk (insert $$$s) in.  
Puh-lezz.
What they should really be asking me is if I think phone cameras are to the point where people think the images captured are as good those that most people can get with a DSLR.
My answer would be something like this.
Phone cameras these days are frickin' awesome!  My phone camera will even generate a RAW image.  How cool is that?  There are apps that will even manage the phone camera settings.  Image file sizes are fairly comparable between the two.  That has to be the same quality, right?
Well, it depends.
Phone cameras make good photography within the reach of most.  The $$$s required are minimal.  After all, the camera is basically paid for.  A lot of what I would call post processing software can be found for free.  Who could ask for more?
The answer begins, as always, is physics.
First, I am a hobbyist.  Not a professional.  And I didn't get too far in physics in high school.  Now that we've set the expectations, let's get on with what is possible and what is fantasy.
The heart of all image capture is the sensor.  This is the same on a phone camera and on a DSLR.
From a very high level, all sensors are the same.  The sensor captures light and translates the information to digital information.  The digital information is captured in a file and you know the rest from here.  To be sure, that is probably 100 steps condensed to 3.  We'll keep it simple.
For the sake of my answer, I'll go with the image capture at the sensor is the best it can be.
If you look up the definition of photography, every one deals with the capture of light and somehow converting that information to another medium.
The key word here is LIGHT.
For most of my friends who are photography enthusiasts, we have (can afford) equipment with what is called a APS-C class size, 23.6mm x 15.8mm for an area of 3.73cm(sq).  Most of us have dreams of hitting the lottery and going full frame which is 36mm x 23.9mm for an area of 8.6cm(sq).  Ah, the quest of light.
So, what's in a phone camera?  Without getting into the math, the APS-C sensor is roughly 18x-20x larger that what is in my phone.  That's the physics part.  I'm sure there is some law that states the bigger the sensor, the more light it will capture.

I can hear the rumble within the Apple community now, well Mr. know-it-all, how come my phone doesn't stink with that kind of math?
You have to give credit where it is due, all those phone engineers earn their money.  Apparently there are tricks in order to get the most possible light to the sensor.  Technology is a wonderful thing.
So the Apple crowd will also ask, well why don't they just put a bigger sensor in the phone?  Well, you'd have to ask Apple, but one reason is with the rush to get smaller and more powerful the constant enemy is heat.  And a sensor will generate heat.
So in the end the answer to the original question lies in, what do you want to do with the hobby?  If you are happy with your phone camera, then yes you can take just as good a picture with your phone camera as you would with a DSLR.  But my answer to the the question is no, my phone camera will not take pictures with which I would create my art.  And it never will.  And I'm OK with that.
My phone takes great 'family opportunity/travel/vacation' shots.  I'm OK with Samsung's algorithms to produce a good JPG file.  However, if I want to show off or print pictures, or as I like to say digital art, than I want the best capture of light I can get.  Or the biggest sensor I can afford.
This covers just the sensor size.  There are other aspects to this conversation as well.  What about the elements of the sensor, the pixel element?  With smaller sensor sizes comes smaller pixel elements, right?  Is smaller better?
How do you get light to the sensor?  I spend a few $$$$s on glass.  Could it be that the lenses on the camera phone are just as good?
Another discussion, another time.

Old Schoolhouse

I found this old schoolhouse on a back road a few years ago, October of 2015.  Not sure I could find it again.  But it is in Michigan, that much I know for sure.  There was a large drainage ditch next to the road, followed by a small rise of debris in the path to the building.  As a result, I couldn't use the viewfinder.  I had to hold the camera above my head and hope for the best.  I have a lot of (blind) shots.  The framing on most could be said to be interesting.  
This was taken with the D90 through the 18-200 lens set to 40 mm focal length.  1/50 of a second, f/25, ISO 200 Aperture Priority.

I like the autumn colors, the orange of the leaves and the color of the weathered roof.  I get the added benefit of some good wood grain which is a personal favorite.  I will suffer with the tree in the front.
In the original image, there was visual junk everywhere.  Back in 2015 my only tool to remove unsightly distractions was to use a clone stamp in Elements.  I played with this image for a while before giving up.
This is the original image.

There were four distractions I need to work on removing.  On the right wall, there is a white tube that is a wire marker.  Just off center right, there is a small tree growing up through the white/gray window filling.  From the lower left, there is a thick horizontal branch that is probably the main objection.  In the upper left, there are a few stray branches the are just irritating.
In Photoshop, I used the fill function set to content aware.  But to use that function you had to use the lasso tool and circle the objects to remove.  I used the mouse, I used the tablet.  The software did the job, but there was a lot more effort involved than I'm used to.  I like easier. So my next effort was with On One's healing tool.  That was much faster.  Just use a brush to highlight the area to clean up, and presto.  That takes care of the overall image.
For my contrasting, even though it is no longer supported by Google, I'm still a big fan of Google's NIK package.  I use the HDR effect module.  In this case I used one of my favorite presets that really over-sharpens and over contrasts.  But instead of going with the total effect, I cut the opacity to 50%.  That was enough to bring out the clouds and the wood grain.  It doesn't look overly altered/butchered.

Rio Grande Trestle

Good afternoon to work on a photo or two.  Single digit Temps, negative temp wind chills.  Perfect day to work on a photo or two.
One of the shots I have from last year's trip to the Detroit Model Railroad Club is of an older model train on a trestle.
This shot was staged for me, as the train was positioned where I wanted it.

This is focus stacked from five shots.  And, as will be shown from one of the originals, some of the background was 'replaced'.
The details: Manual Mode, 32mm, 1 Sec, f/8 and 200 ISO.

Here is the middle shot:

I used Helicon Focus (Pyramid Method) to merge the five shots.  I was pleased with the outcome.

I used On One to remove the office wall.  

I had a photograph from a trip to New York a number of years ago taken on a hike to a waterfall.  The background matched up pretty well.  The sky had a little color and the trees in the background came close to matching.

I used Google's Nik HDR effects to top it off.

Good project for the day.