I think the reason bubbles down to the fact that people are used to TVs being dumb TVs with a remote that everyone knows how to operate. But the abilities of these TVs are growing exponentially compared to what people expect so they have to find a middleground by having a remote-looking pointing device and a TV-looking interface for this computer with a giant screen.
Eventually I believe it will evolve into something more functional.
These machines are almost impossible to operate without a remote. But remotes are not standardised; nor are the UIs the machines present. As a consequence, I become the only person that can efficiently operate my TV. And when I switch TVs, it takes me a month to learn how to drive it. The girlfriend doesn't have a chance.
Maybe I'm just slow on the uptake.
If TVs were cars, each brand of car would have different arrangements of controls; some would have a joystick for steering, some would have manual accelerator lever like a boat, some would have a horn operated by a foot-pedal, and they'd all have completely different gearstick locations for the different gears.
I need three different remotes to operate my TV: one for the TV, which I use only for switching inputs; one for the Sky STB; and one for my audio amplifier. I need all three to set up a viewing session. This is nuts, not least because none of these remotes is specific to the device they're paired with; each of these remotes has non-functional controls that are obviously meant for some other model, because they have no function or meaning with my model.
Disused remotes pile up in drifts in a cardboard box in my spare room.
Maybe in some distant future, the industry will come up with a standard for remote controls and user-interfaces, such that once you know one, you know them all, and so that any remote can be used to control any A/V device. This would drastically reduce the number of prefectly-good remote controls that end up in landfill.
This is kinda what HDMI CEC is (https://en.wikipedia.org/wiki/Consumer_Electronics_Control). When I push the button on my AppleTV remote, the TV turns on, the receiver turns on and switches its input to the AppleTV. When push the power button again, the TV and receiver both turn off. Same thing when I grab the Playstation controller and turn it on.
I have a remote for my receiver and my TV, but I never ever touch them. The nice thing was that the only configuration required was to enable CEC on the TV and receiver. Everything else just worked.
Eventually I believe it will evolve into something more functional.