I don't think it's "aged" any worse than SNES. You're just reading your own [changed] preferences into it.

I had SNES since launch despite a prior love affair with wanting Genesis (the Genesis Does campaign had me convinced), but Genesis was popular and I had friends with it or both. I definitely played more SNES, and my later years in high school, late 94 through 96, I was somewhat of a lapsed gamer.

The point is, I keep discovering Genesis games from that period that are awesome that I never played and I find them no less fun or impressive to my classic gaming sensibilities than SNES games.

I do think that a lot of Genesis sound effects are an 'acquired taste' when they use FM instead of PSG. They gave birth to the muffled robot fart meme Sega fans hate, and if you never had that taste, experiencing them now may be off putting.