The Pi 400 is still a fantastic device that I was late to the party on getting. it hearkens back to the age of the personal microcomputer from the 1980s where the keyboard and motherboard are contained in one device with the business end of the machine on the back side of it. Incidentally, Apple applied for some patents for doing something similar again.
It’s just a fun thing to use for many reasons and it is a great device for kids to learn and experiment. I have been using openSUSE Tumbleweed on my Pi 400 and have been enjoying it quite a bit. This video I demonstrate how well openSUSE runs on the Pi 400. I think it is possible to have a “NOOBS” version of openSUSE for the Pi and I demonstrate it here.