Technology

The best solution os actually to keep the decoder smarts separate from the actual displaying of image because those two things have different life-cycles and different costs.

A decent TV screen will last you decades and work fine at doing what it does, with the only pressures to upgrade being video connectors - which change maybe once every 2 decades and usually you can use adaptors to give them another 2 decades or so of life - higher resolutions - which make no difference unless you have a very large screen, something which requires a large living room to view at the optimal distance and in which case what really drove you to replace it was not obsolescence - and screen tech advances - which is another of those "every couple of decades it changes but the old ones are generally still fine" kind of thing.

Media Playing, on the other hand, has its life-cycle linked to video encoding and compression which change every 5 years or so and either you have a seriously overpowered generic CPU there (which smart TVs do not) or you have hardware decoding, and in the latter case new video encodings require new hardware with support for them.

So your TV with built-in decoding - i.e. "smart" TV - will need to be replaced more frequently driven by the need to support new digital formats, even though the part that costs the most by far - the screen - is still perfectly good. On the other hand if your media player functionality is separate, all you have to replace with some frequency is the much cheaper media box whilst only replacing the much more expensive screen side once in a blue moon.

Smart TVs are great for manufacturers because they force people to replace the TV much more often hence they sell 2 or 3 times more TVs, but they're in the mid and long term a really bad option for actual buyers who needlessly spend much more on TVs, not to mention Ecologically with all those perfectly good screens ending up in landfills because the $20 worth of "smarts" tied to a $1000 screen is not capable of handling new video encoding formats.