I think you meant "microcontroller", the Pi 4B for instance is powered by a 64-bit quad-core ARM A72 running at 1.5 GHz. That is most certainly what most people would call a (rather beefy) microprocessor.
You’d be surprised how far you can get with an ESP32-S3, the Xtensa LX7 is a weird little chip, but surprisingly can be quite powerful. Though I’m biased of course because we use them to their limits at work!
It’s not out of reach for hobbyists, I think, though getting it to run very well might be. And I would certainly tell anyone interested to start with something more powerful first!
I’m currently experimenting with porting Arraymancer to the S3, just to see how it can run, outside of work time mind you.
Slightly orthogonal to what we are discussing above, but more to show that these weird micros have some surprising grunt if you know how to make them sing.
Though I still wish ESP-IDFs malloc was better behaved.