I don’t think the pink colour scheme is bad, but the way the theme is implemented is simply eye-searing. Please make the background dark grey, tone down on making everything different shades of purple, keep it to accent colours. Like Purple Smart said, people can just change it, but I think the default should still look pleasant on the eyes, because it’s the first thing people see when they open the site.
I’ve also seen suggestions for an Aryanne-inspired light theme (who is basically the free speech mascot and a big reason why this was created right now) and/or an Angel Wings theme (because Zizzy, and at least it would make sense as a pony-inspired theme, rather than this weird purple which I honestly do not see the symbolism of).