Imo it’s not enough of gap to be a big deal, there are much worse age gaps, especially when you’re talking about only people above 21. I’ve often dated older and when I was in my early 20s I would go on the occasional date with someone around 30 and the biggest reaction I got from friends or people around me was light teasing, but most didn’t really care. Now that I’m 30 I don’t feel that uncomfortable dating down to around 25, but I also look young and don’t feel like I’ve matured that much since my 20s.
I don’t think most people would care at the end of the day, I feel like it only becomes weird when you’re like in your 40s dating down to 20 something.