This is not about Newpipe itself but more that fact that this is an Android app ran on desktop Linux, without any containers like Waydroid does. This is like Wine, but for Android apps.
FreeTube doesn't always have 4k. I don't remember which format, but a video has to be a certain format to show as 4k. Majority of videos that are shot in 4k show as only 1080p on FreeTube. I welcome new pipe to linux and will actually be using it
Well, good news the newest update to Freetube now adds 4K+ support since they changed the library used to get the videos or something. I have tested it and the video says 4K and seems to be that. Feel free to correct me if you try the latest update and find any discrepancies.