They do and they don't.

Ever been to a high school / college reunion? People slip back into their old cliques within half an hour or so, as inevitably as gravity. The ultra respectable bank manager is once more the wisecracking fool, the meek accountant is once more in his glory days as a jock and the rapper turns back into the quiet geek he was.

That is harmless, a temporary reversion to a more innocent time.

What you are looking at in your question is a guy who simply hasn't changed. Your guy probably simply stayed in the popular crowd all the way through, where others are there simply to make life easy for him and to do his bidding. Easy to stay self centered and unaware that others have feelings in that case. Tempting too.

You constantly hear the refrain "People change as they get older." It's a load of crap.
People change because they are forced to by outside circumstance. Not because of numbers on a calendar. And they usually hate it and search for any way out of changing a single thing about themselves.

Let me tell you a short tale about two pretty and popular girls of my aquaintance. Both at the same high school, both popular and in with the in crowd. Both pretty well off, too.

One, after high school, went to the local college. Lot of her friends went there. She slotted neatly into a sorority and carried on. High school hadn't ended for her. She left college and got a job in her Father's business.
The other went to the city to make a go of it as a model / actress. Where she found several thousand young women. Just as pretty, just as flirty, just as fun.

Guess who grew up faster.

For the tl:dr crowd - some people never change. The rest of us have to.