People that don’t want to think about their photos use a smartphone. People that want to think about their photos still want a camera that they can control. I use a mirrorless Nikon camera and to take a single picture I normally want physical controls that can handle exposure, focus, zoom level and shutter release independently, but simultaneously without having to remove my attention from the image. The ability to do all that with physical, not menu controls, is a tremendous asset for most people that want to spend the money on a camera. If you slapped the latest technology inside a camera that didn’t have all the physical controls, photographers wouldn’t want anything to do with it.
I wouldn’t say that camera design is stuck in the 80s, either. The form factor is necessarily constrained by needing a tubular lens projecting in front of a flat imaging plane. The photographer is going to want to view the image from the opposite side as the lens. There’s only so much you can change the form factor with those constraints. Camera companies do have a few retro models, but even stodgy old Leica is making modern designs these days.
If you take tens of thousands of photos per year, you sort of realize that all cameras have more or less the same interface and form factor as they have for a while because it is what works best.