I am reasonably pleased with my TV UI approximation. It’s an old Skylake-era CPU running Windows 10 Enterprise IoT LTSC which lasts until 2032.
I chose windows because Linux is often limited to 720p browser streaming. And I got tired of overcoming hurdles to make the thing work well, forget what they were but damn they sucked and took a lot of time. Burned through a ton of my self-allotted time fixing stuff till I just ripcorded Win 10 Ent IoT LTSC; Linux might go better for you!
Anyway, it’s at 150% desktop scale and I have the task bar auto hide. I have icons for all streaming sites, Freetube, and Jellyfin on the desktop arranged in a grid. It looks reasonably good, they open in Firefox or in their apps. I close the whole window when I’m done (I don’t use the browser’s tabs), which helps with the “TV box” feel of usage.
I have a remote that has some IR functions to turn the TV on and off and change inputs along with gyro mouse control. It’s hella China, just buy one on your relevant China source (Amazon, alibaba, etc.) - there are tons of clones. The light up feature on it makes an audible hum, so that sucks, but I don’t use it and don’t seem to miss it.
Best bonus is it blocks ads on all the streaming services I have (uBlock origin mostly, also AdGuard but I think uBlock Origin does the heavy lifting). And can turn on WireGuard for modern account sharing, going to automate it soon for certain streaming services.