I got the gen4 so I could have apps and better LiveTV streaming and so on. But this tvOS11 is horrible. I'm a freaking cross-platform developer for a living and I look at this as Mumbai outsource junk!
If you have an existing library they have lobotomized all the ability to do anything decent with it. Hundreds of shows and movies on my server. I have capped satellite internet so I can't just freely stream everything as if I was on fibre. I buy DVD's and rip them to my server. I buy and download from I tunes, Amazon etc. and keep everything as a local file so I can then put it on my iPad, iPhone7+ etc. and watch off-line: You know, like when on a plane or cruise ship. But Apple has taken away core abilities like "unwatched" or "by air date" from TV shows and movies. Do these people not even use their own product at home to confirm it makes sense and is functional?
If you want to downgrade act fast while the os10 bundle is still signed. There are tutorials on the 'net.
I'm strongly looking at replacing my 4 AppleTV's (3xgen3, 1xgen4) with some simple Firecast stick and replace all of iTunes with Plex on my home server. That's how bad this has gotten.
Get the Cook out of the kitchen and put some actual developers back in charge of development.