I think the op’s point was less about the difference between people in their 20s and in their 30s, and more about the difference between a 50something dating someone in their 30s, versus a 50something always seeking out 20somethings and even dropping their girlfriends whenever they reach mid 30s, for a new 20something partner. 50something and 30something is a huge age gap (nearly half a life) but there is quite a degree of acceptance of 50/30 relationships, compared to 50/20 where you’re dating someone who would potentially be younger than your own child. Elon Musk seems to systematically seek out partners half his age, and long before MeToo or wokeness, that kind of thing was widely regarded as skeevy.