Good day! I am trying to find a good alternative as not to use the"smart" functions or using an Xbox to consume our media. I found a few options ie like plasma big screen but it's no longer in development. Essentially I would line love to have it running on an rpi4 and just hooked up to the TV.
The option(s) other commenters gave are great!
But just to give you more options, I'll give you a few additional ideas.
KDE Connect: You can still use a normal desktop (preferably KDE or Gnome), set your display scale to 150+%, and then use your phone remotely to control the cursor, media playback, and more.
Bazzite: often used to replace SteamOS, it also boots into Steam big picture mode by default, where you can set applications in the start menu. It has a nice console-like interface, and you don't have to maintain anything, e.g. updating. It also supports Waydroid and webapps by default.
An old laptop or mini-PC with Bluefin or Aurora. They are basically like Bazzite, but without gaming stuff. You can set the display scale to 200% and enjoy a worry-free experience. Optionally, you can install Phosh or Plasma Mobile on top, which is made for mobile devices.
Except the UI is not designed for that. I want a TV interface that is controllable via a remote either physical or virtual. I'm not going to try and deal a full desktop. If it takes me more than a few seconds to do something that's way to long.
KDE Connect has a remote feature for presentations. Maybe one can create a small interface/ WM for it?
For example, Niri WM, configured with just left, right, and laserpointer as confirmation button. Based on uBlue, so it updates itself. Does that sound practical?