Why Mint over Ubuntu? I've only ever used Ubuntu...but I'm not married to it.
Mint is basically Ubuntu without snaps. Snaps are universal cross-platform, but at the expense of being slower to open. The majority of Ubuntu software works on Mint. There's other reasons but this would turn into a novel. Maybe we can make an article on this topic? Would that interest you?
Mint is faster than Ubuntu, it's running like a dog on any hardware.