iirc one of the biggest differences between Ubuntu and Linux Mint is the store that each distro uses.
This link describes it better than I ever could: https://linuxmint-user-guide.readthedocs.io/en/latest/snap.html
TLDR: There were backdoors and weird behind-the-curtains stuff going on with Ubuntu’s store, so it was axed by the Mint team.
The Wind-Up Bird Chronicles by Haruki Murakami