Played it last year. It holds up, much better than you'd expect it to.
Unfortunately, can't tell you why, because explaining it would vastly diminish the experience
Mother 3 is a game I wish I could re experience for the first time. But with EB on switch now I have a huge urge to play it again. I think the big reason it works is that not only does it do the quirky game thing well, but it has soul. It has heart. Unlike a David cage game, it packs emotional punch and it will hit you hard in the gut if you give it a chance.
I know people say "This game has heart/soul" a lot but this game really feels like it was a work of passion rather then something done to make money(because EB and M3 didn't really make much money, the advertising for EB in NA being part of the problem). It helps that the
guy who made the mother games is something of a loon, but in a good way(
apparently he's spent years trying to dig up a mythical japanese treasure) because started out as a copywriter who wanted to make games rather then a game designer(and he's into a bunch of other stuff, among them acting and writing).