Travel OS, so I basically browse the Internet, watch some videos, listen to some music and do some hobby projects. Also it's nice to have a not so expensive laptop for travels, so it's not such a big deal if it gets stolen. And of course the travel machine uses full disk encryption. Size is important here: I prefer 12" for travels and 14" for work, when I want to view multiple files at the same time.

OpenBSD has hard time using even 4 gigabytes of RAM with Firefox having multiple tabs open. My Arch installations easily take over 8 gigabytes, if I'm not compiling anything.

If I need a backup machine for work, I kind of want a Linux with all the Docker, Spotify, Signal etc. easily available.

That sounds like a hefty OS. My Arch install is currently using 4Gb, and this is a full desktop.