What do you use your TV remote for? At my parents' house we have a TV and a cable box, each with its own remote. The only reason to use the TV remote is to turn the power on and off. All the other functionality is in the cable box remote.

Turning the volume up and down. Which leads to another point I forgot to mention: people expect TVs to have built-in speakers, but a lot of monitors don't.

Maybe, but smart TVs - and dumb TVs too - have pretty bad speakers. It seems like having a "soundbar" or equivalent is more common than not.