our smart TVs? Do you know any modern TV with smart functionality that doesn’t require us to use Google account?
So…I think there is a mixed bag of news here - this is what I’ve come across…
First off, let’s help improve what you’re searching for. The terminology has largely changed; what used to be called a “TV” (i.e. a display panel that shows a signal given to it from a composite/component/HDMI source) isn’t called a TV anymore - it’s called a “Digital Signage Display”, or possibly a “Commercial Signage Panel”…something to that effect. They’re dumb displays - they show the input they’re given, and that’s it…can’t get much more de-googled than that, so if you’re searching to purchase something, that’s a good place to start.
Assuming you have your own TV…the answer is a bit trickier. My GoogleTV based TCL TV is ‘degoogled’ in that I’ve denied it access to the internet. Can’t send Google any data if there’s no network connectivity. I was relatively fortunate though, in that there was a ‘set up without internet connection’ option. If your TV doesn’t, then you may have some luck with a bait-and-switch - change your wifi password, set up the TV, get to the point where you can choose an HDMI input, then change your wifi password back to the original. So far, I haven’t seen any TVs that prevent a setup in this manner.
In terms of replacing firmware, that’s much more complicated to do on a TV rather than on phones. The single biggest issue is fragmentation - TV manufacturers change up their models multiple times a year, usually per-retailer - you won’t find the same model TV sold in two different places, which means that every year, there are hundreds of different models, from hundreds of different vendors, all of which are just-different-enough to make modding a much more difficult proposition, and only a few dozen people at most would use it because of that.
The second big issue is that streaming services require WideVine. While a phone can be entirely useful without Netflix/Hulu/Disney+/HBO Max, a Smart TV…basically isn’t. Aftermarket firmware would have to support WideVine, which is so dependent on Google’s Play Services, that there’s really no way to make an AOSP TV that is anything other than a signage display with a web browser…puts a bit of a damper on the proposal.
Now…assume you’ve got something that can show HDMI1 and do little else…that’s fine, because we can have the OSS-part on the far side of the HDMI cable. No problem. LibreElec runs on a Raspberry Pi; grab a Media Center remote and receiver for $25 on eBay, sounds great…sort of.
I did that for a while, and - at least at the time - it wasn’t worth it. It’s great if you have a Plex/Emby/Jellyfin library, but it goes downhill fast after that. Youtube requires a developer account (i.e. login + connection; no ‘guest mode’ viewing). Hulu worked, but Netflix requires a whole rigamarole that involves pulling some files from a ChromeOS installer (not-very-degoogled), plus I had some issues with TV episodes randomly playing in black-and-white. Disney+ was a cat-and-mouse game. Amazon Prime Video wasn’t available at all. Standard cable TV was out too; I always wanted to set up MythTV with an HD HomeRun Prime, but sadly my cable company added the CopyOnce flag to everything (even public access!!), so that was a nonstarter. This kinda makes the core utility of LibreElec as a frontend for Plex/Emby/Jellyfin; the utility is rather limited for official streaming services. As an added bonus, a Raspberry Pi + accessories will run about $75, give-or-take, while a Roku (and all its proprietaryness and analytics, etc.) is less than $30 most of the time, AND it works with everything.
So, I think there are a number of parameters involved with why it’s not more popular…but hopefully that information will help you decide what you’d like to do.