if it can upscale 1080 ti 4k, does that mean I don’t need my 4k collection anymore? It sounds too good to be true.
Because it is. While it does do a decent job upscaling, it's not some magical thing. Keep the 4k, and be pleasantly surprised when older content looks nice on the larger display.
The android tv app is why I switched to Emby. I mostly liked jellyfin everywhere except the one place I would use it the most.
A few of the fixes for things that strongly turned me off were added as feature requests, but the devs seemed to blow them off as unnecessary or "impossible" (even though the "impossible" is done in every other android tv app, including Emby). Their perceived attitude really turned me off of it.