YouTube's default UI isn't too bad, in my experience, admittedly my tv is on the small side. I use slightly increased scaling to make things bigger. I use jellyfin and it's default web interface works well on a tv, I haven't tried the desktop app but it's there. I used to use Kodi and while it did present a much more TV centered UI, getting each app working was a matter of managing different third party plugins that would break on me frequently. I used to use Freetube, which both blocks ads and includes sponsorblock. It lets you use YT mostly without an account, including subscriptions, playlists, watch history, etc. It takes some fiddling to import your subscriptions if you do use a YT account.

Using the mouse and keyboard on my phine via KDE connect is my default and works well for the less TV centric UI.