Samsung seems to understand that TVs get upgraded at a slower rate than the TV's smarts evolve and that software updates can only get you so far. They have started to ship something named the Evolution Kit. For around $200 it allows the user to unscrew the CPU module from their existing TV and install a more modern CPU/software combo.
Completely worthless. The CPU in a TV is never the problem. That's why they use such low powered CPUs to begin with. Nobody even makes a TV with a Core i7 even though there is no technical reason why they couldn't, because there is no demand for it. All anyone cares is that it can decode video at the native resolution, which the original CPU will be able to do until all the pixels wear out.
Well, power is a huge concern. We were looking at CPUs embedded in TVs, and 10 watts was about the limit for the processor board.
Regulations (esp in the EU) get into the game as well.
Life is better as a component that attaches with a cable. You can't really put a gaming console in a TV, not yet (not one you'd want to actually use, anyway).
https://www.samsung.com/us/video/tvs-accessories/SEK-1000/ZA