Debian. Several reasons:
- It’s trustworthy.
- It’s not going anywhere. Debian existed when I was a kid and it’ll probably still exist when I draw my last breath.
- I know how to use it, since, once again, I’ve been using it since I was a kid.
- It has all the desktop environments.
- It fully supports systemd. I do not miss the unreliability, slowness, and complexity of what came before that. (Normally I wouldn’t mention this, but your former distro of choice exists solely for the purpose of not having systemd, so it’s relevant this time.)
Global warming is upon us. If something doesn’t drastically change, now, our entire species is going to die.