I found it a real struggle with the TV to find a non smart one, especially as the smart ones are cheaper. Best bet is to get a TV stick and never connect the TV to the internet
I have a Nvidia Shield (bought used on eBay) and works fine with my LG Smart TV, which has never touched the internet. I have a Xiami Mii TV S on another TV, which is the closest to stock android TV I found. Do not get a firestick! Both have 4k, can control TV volume through the remote, have auto turn on/off, plus the TV just goes to that channel so don't have to touch the TV remotes ever. The Shield is faster and easier to setup but much more expensive.
You could also buy a mini PC but can be harder for certain apps and full video and sound quality (avoid if you want Netflix and other apps). I have stremio (with Real Debrid), jellyfin and TiviMate (IPTV) for all of our needs so could get away with a mini PC but considering the effort I decided not to.
Not sure about the sound bar as bought sonos years ago. It works flawlessly with the TV and runs through home assistant now (responds to Shield remote volume control or can play music through HA BUT I set it up with the original app so can't comment on that part). It has great audio quality but agree that I would look elsewhere if looking now (although would still consider it).
I also use pihole to try to block any trackers etc.