Even higher end brands like Samsung are pulling stuff like this.
Market forces demand constant growth, and in a saturated market this means some business unit manager will keep adding more invasive advertising as long as people keep buying the TVs.
I've had good luck with TVs from Sony, which would probably be considered higher end based on price bracket. They ship with near-stock Android TV, don't make a fuss about not being connected to the internet, and allow firmware updates via thumb drive. Have had a couple now that I use with an Apple TV, which is a pairing that works very well.
I wonder if Sony are releasing the Linux source code they run Android on and I wonder if their firmware updates are signed. If they do release source and updates are signed, you could probably install a regular Linux distro with Kodi.
Likewise, but the problem now with the built-in software is that Android TV is getting increasingly user-hostile as well. The major UI update they made which added an uneditable promotional section to the top of the home screen eg.
