We contacted Sony asking about creating an app. The TLDR of that conversation is they said "Don't call us, we'll call you". Open source never really mattered, they're not interested.
Jellyfin supports 4K HDR playback depending on the client. I don't personally use Infuse but I believe it supports 4K playback depending on the hardware it is running on.
The only data Jellyfin "collects" is the download count from our mirros, which resets every ~24h, and can be viewed here[0]
Note that this number is a count from all of the mirrored files, not just the server.
We’ve been using Cloudflare pages for Jellyfin’s experimental client[0] and it’s been really nice having automatic deployments on each PR and automatic master builds.
https://immich.app/