Old school user here, back in 2005ish Ubuntu was straightforward, even had “wubi” to install it as a windows app, the site was friendly and easy to navigate (compared to Debian’s). Another big plus, they shipped the distro CDs for free worldwide, which was a big deal while I was stuck on a shitty ADSL connection that had constant drops.
Mint came a bit later and the big plus was OOTB codecs support. Back in the day that was one of the first walls most users came across, while Ubuntu pushed for a paid mp3 codec (fluendo?) Mint had most audio and video codecs working right after setup.
The UI wasn’t that different between the two, considering Ubuntu was running gnome2 (what mate immitates nowadays)
I kinda use most of proton’s stuff. Also I’m not on the us so no idea what the second part means