Discord would be the obvious answer, but I understand why you might want to use it, my recommendation is using a client that disables some of the tracking like Vesktop. Spotify is also a major privacy concern, it can be replaced by Spotube (and to a lesser degree by Audiotube) which removes most tracking and is three and convenient. Also I’m not sure if I would keep using chromium, especially with manifest V3
Bazzite (fedora based) is actually more like steamOS than Arch is like steamOS, as both Bazzite and steamOS are immutable. I love Bazzite/Aurora/Bluefin because they have the option to include Nvidia drivers preconfigured out of the box. There have been some improvements in KDE for NVIDIA recently, so maybe check it out. One quick question, why is dealing with packages a pro point for Ubuntu?