"There has to be SOMETHING there"
If you took your head out of your ass you might see that there is something there

Mario has always had more of a bond with Bowser than with Peach. Peach barely has a personality, and what personality she does have consists of keeping Mario just close enough that she can call for his help whenever she's in trouble, always rejecting him whenever he tries to get closer. Bowser, meanwhile, has maintained a healthy rivalry with Mario over the years, sometimes even setting aside their quarrel to face a larger threat as friends, if only for a short time.
The original Bowsette comic just set off something that's been simmering since Mario Odyssey's ending: Peach is a thot, and Bowser and Mario are both better off forgetting about her. All the better if Bowser becomes a cute girl and they could be happy together.

People may come for the sexualization, but they stay because there IS more to it than tits. The concept of Bowsette is great, that it's this badass princess that's totally contrary to Peach, and it's fun envisioning her in different situations with Mario and everyone else. And the Super Crown allows us to be creative and see how DIFFERENT characters would turn out if they've been transformed into a princess. Yes, lots of tits, but there are also CUTE, non-lewd interpretations (it just can't be helped that dudes love boobs). Really, it's just the amount of potential behind all these.
And FYI, people aren't downvoting because you have a different opinion. You're downvoted because it's a SHORTSIGHTED opinion. You look at this gallery and think, "oh, they're all just horny." A fair assumption, I'll give you that, but if you're gonna make a bold claim about everyone, you should realize it DOES actually go deeper.