I just run stock ubuntu with an airmouse, freetube, a browser, and kodi. Works just fine on my projectors and tvs around my house for me and even non technical guests.
Yes, and I have done the same for a long time. It works, and the browser is key when you don't have native apps. But I recently spent some tokens on an Android x86_64 TV build with ARM support and it is far better than a Linux DE with the scaling cranked up. It's all scaled correctly, the UI can be navigated with the D-Pad alone, and all the apps are also designed that way. It's a massive improvement over a UI primarily designed for keyboards and mice.