As others have said, just buy a TV that meets your A/V needs and don't connect it to the internet.
I know everyone talks about Jellyfin these days, but Kodi is an excellent option too if you don't need streaming to multiple devices. I use Kodi via LibreElec on an rpi4 and it's been great. All media is stored on my home server and shared over Samba, but you can easily store it locally on the box if you don't have a server.
For music streaming, I run a separate instance of miniDLNA on my server, since I like to browse-by-directory for my music instead of relying solely on metadata. This also allows you to stream to any DLNA-friendly device on the LAN.
I've digitized my disc collection and just keep the physical media as a backup. The local library has a huge selection of media too...and if we don't use it, we'll lose it.
I have a JF instance running on Proxmox as well, but it hasn't won me over yet. Still, I know a lot of folks do prefer it to Kodi and others so there must be something to it.