Basically, the Smartphone replaced the POCKET point and shoot camera. Their market are overlap each other. If I already have a pocket size Smartphone which can take decent photos within its limit, why do I need to get another point and shoot camera that do the same.
Technically adding feature is one thing, adding a feature that nobody want is another thing. Another of the DSLR or even Mirrorless cameras are not pocket-able. Yes, the mirrorless camera body can be small, but the lens is not. And certainly not able to put it in the jeans pockets.
I am sure if you setup a poll and ask most of the photographers here whether they are willing to pay a little more to buy a DSLR or Mirrorless camera which is also a smartphone. i.e. Sony Mirrorless Camera $600, Sony Mirrorless Camera with Smartphone $900. (which is going to be a lower to mid range smartphone)
For me, I will pay a little more to get a Camera and a Smartphone separately. When I go pay at the cash register, I'd rather pay with a phone or watch. When I relax at a sofa browsing Reddit, I'd rather browse with a phone. For sure when someone call me, I'd rather pick up the call with my phone. Imaging holding my DSLR with a 70-200 f/2.8 next to my ear and talk. Well, at least I can tell the person at the other end, "Hey listen, I need to go and talk to you next time. My arm is very sore!"