I'd assume he just forgot about them. He's 29 now so I guess he tweeted them around 15, that's pretty young to be held accountable for the rest of your life for something you said. I haven't seen most of these tweets so maybe they're way worse than I'm assuming.

The insecure, cringey adolescent sexually-related stuff is sad but most people go through phases where they've said and done things they're embarrassed about later. I would hope some of those weighed less on the decision to cut ties, though with a tenure of several hours, you haven't earned any leeway in a position like this when it comes up.

The "I'm not racist...but" lead in to saying "Asian people piss me off" is not someone who should ever be employable if they want a public-facing job, or really any job. I have no problem with that shit following him around--if you made it to 15 with that kind of intolerable bigotry you missed some important shit and life has consequences for it. Sucks he or his parents or his environment were late getting him (or others like him) the message, but there needs to be a clear division between "you're entitled to your opinion" and "there aren't potentially serious future consequences for bigotry and there is no hiding from them."