Do u assume ppl have matured for the better?

So i was outside today and i saw some1 i knew from my early highschool days. He was a lowkey-bully of mine and by that I mean he was a petty vengeful ex who childishly befriended and gathered my other exes (they were all from different classes) to hang out multiple times in my classroom during breaks to make me feel uncomfy. i was going thru a lot at that time n depressed n isolated from my gang cos i was the only one among my friends who made it to special advanced class. So basically it did a lot of psychological stress to the insecure teenage me who felt like a cornered slutshamed laughingstock. But ofc to them they were simply hanging out together plus their other friends in my class. I did try to view it like that at first and ignored them but i started leaving my classroom during breaks when I overheard them actually talking and laughing about me and i wasnt gonna stay for any of that bs.
Anyway I saw him and he probably saw me too but we didn't interact. And i wondered how i should see him as a person now that we r adults and that HS thing was more than a decade ago.
The thing is, the teen mind is drastically different from the adult's and he definitely isnt that petty teen anymore. But how do u ppl see your old then-teen now-adult "enemies"? Do you automatically view them as foul as they were before? Or are they a completely new person now who simply did silly teenage decisions when they were younger?