This “dumb tv” trope comes up in every one of these discussions. We are the minority and most people want a tv with a Netflix all and not to have to buy a set top box. There isn’t a market here.
While a developer, this kind of work is outside my current wheelhouse and I just don’t have the time to learn and fork it myself. So throwing out my desire. Half hoping someone out there wants it more than I do.. and half just expressing my frustration with modern TVs.
Often smaller installs / live events people want simple non-smart screens for all kinds of things (on stage, in waiting areas, musician cues, info to crew, signage, etc), and although it's possible to buy expensive "monitors" that do it - being able to use cheap and large domestic kit with much faster startup and no extra crap, and no logos being displayed while booting or if it loses signal or whatever would be very desirable.
I can assure you there is an even smaller a market for a reverse engineered open source LG TV firmware.
As an extreme case, Linus Torvalds decided to write a terminal emulator, do it straight on the bare metal for his PC, accidentally deleted his OS in the process, then got carried away a bit trying to survive without real OS. None of these decisions made any business sense, yet we have the entire Linux ecosystem out of it.
I’m a “hacker” with multiple LG TVs around the house (in fact I exclusively buy LG TVs) and I have no interest in putting custom firmware on those TV sets. So I can’t imagine there’s many inside the Venn bubble that are both laymen enough to want Netflix, technical enough to know about custom firmware but also motivated enough to want to install it.
So the number of people who want dumb firmware might not be disproportionately less than those who want custom smart firmware.
Not wanting to commit digital piracy makes you a "layman"? What other options are there? I'm assuming you're using "Netflix" as a placeholder for all similar streaming services, but even if not, there are still many shows only available there that you simply can't legally watch without it.
Making a firmware that does "nothing" is probably less work than making one that does a lot of things. So even in the new currency (developer time) it might be cheap and make some people happy.
Which is GPs point. Open source TV firmware means that the manufacturers motives are no longer the totality of the conversation.
It'd be great if say Google pushed TVs in this direction ("Google Display with smart cube. Never have an outdated TV again" or something), but I bet the decommodified dumpster fire of baked in software benefits them too much. After all, the last thing any of those companies in the business of selling "content" wants people to do is to end up plugging in a Kodi box. It's like banks with overdraft fees - by abusing your customers, you make them worry that switching will result in even more abuse, thus encouraging them stick with the abuse they already know.