I heard this recently and think it's pretty interesting. I'm not sure if it's the best definition I've read, but it's more practical than other ones, so is useful from that perspective.
“He who works with his hands is a laborer.
He who works with his hands and his head is a craftsman.
He who works with his hands and his head and his heart is an artist.”
- Saint Francis of Assisi
I'm 100% for not gatekeeping. Even from a practical perspective, saying someone/something is or isn't 'art' doesn't mean anything, and people who like to be critical are really just telling us about themselves, not the thing they're talking about.