I'm personally of the belief that the Mario "main series" consists of the platformers*, Kart, and Party.
*sans the Land duology, Run, and the spotlight games marketed as sequels. I'd probably also be reluctant to count Mario 2 if it weren't for how heavily it impacted later Mario titles even if it never got a true sequel or successor.
*sans the Land duology, Run, and the spotlight games marketed as sequels. I'd probably also be reluctant to count Mario 2 if it weren't for how heavily it impacted later Mario titles even if it never got a true sequel or successor.