Yep, lots of things like cars, home appliances, home theatre components, etc. get regular, if not yearly, updates even when some of those things have a 10+ year lifecycle for the average consumer. It’s not like Apple stops supporting devices after a couple years. With things like the Apple TV that aren’t updated as often I end up putting off buying something that I want because, like you said, it might already be 2+ years old and I wouldn’t want to feel behind when the new one comes out less than a year later. I’d rather see smaller updates more often so there’s always something recent when I’m looking to buy.
Cost, and having something dedicated to the space. Maybe also that it controls your smart home stuff so you want it to stay in place and not be taken out of the home. I can see something comparable to an Apple TV with a built in display/speakers/camera. Don’t need much power, but something that can run your streaming services, YouTube for cooking videos, and a FaceTime camera for calls would be neat.