I agree with most folks here that usability-wise, both are truly fine! Mainly I think philosophy is where Mint might have an edge here.
Ubuntu, run by a corpo named Canonical, has had some controversial decisions in the past, such as inserting amazon ads into the system's search feature, or "opt out" analytics being default, and lately, a system called "snap."
Snap is controversial because it has a closed source backend, but effectively works just like its open-source counterpart, the "flatpak." It's packaged so the software has everything it needs to run.
Some people say they work great, others hate them, but Ubuntu doesn't make it very easy for you to have a choice in the matter.
If you don't like the idea of snaps, it's a bit of a pain to get rid of it. And otherwise, Ubuntu will sneakily use it as the default way to install most software. Philosophically, this can feel a lot like why people left Windows behind!
Long term, that's why I favor and recommend Mint to most newcomers: It doesn't play those games, sometimes the drivers work even better, the community is fantastic, and the vast knowledge that works on Ubuntu should work on Mint too.
So that's mainly where the difference will lie.
Either way, I wouldn't sweat it too much while you're learning, as long as it does what you want! And purple-orange is pretty snazzy. ;)
Mint just feels a little "cleaner" in my humble opinion. Most software you'd want the latest of, like GIMP or Discord, will be found as a Flatpak in Mint's app store.
Hope this helps you get a clearer view!
I also love Tumbleweed and rock it as my daily driver!
To complement this point, OP, you can also get that sweet rollback functionality in any distro! Usually the easiest way is selecting BTRFS as your file system on install, and installing a software called "TimeShift" that will manage snapshots for you.
BTRFS can be complicated, but basically, it allows remembering the changes in files, without needing to copy the ENTIRE file. This saves a ton of space. (You don't need to get into the weeds deep diving if you don't want to. Snapshots are great, everything else is great, as long as you aren't doing crazy specific RAID setups or something lol)
Otherwise, on EXT4 for insurance, your rollbacks would just literally be copied files, which can eat your storage fast. :)
Tumbleweed is known for rolling (heh!) this in quite smoothly by default, but this is just an example how any distro can be tweaked how you like! (Highly recommend setting up Timeshift on ANY install.)
I absolutely second the advice in this comment: Try some live USBs or virtual machines and just play around for what feels right. Distro hopping can be lots of fun, but you'll find one that "feels like home."
:)