Earlier quoted context omitted.
We all know when it happened, but it was ordered and scheduled by Trump. Biden actually stayed around six months past that point. By the time Biden took office, there was only a token force left there (in fact, Biden sent more troops). Source: I was in the military and had friends there.
Smells like both. Trump made a bad deal, perhaps knowing he was able to leave a poisoned chalice behind. Once Biden came in, he should have reviewed it thoroughly and not gone along with it.
Anyway, under international law, you can’t exit a treaty so it wasn’t even an option. Where are you getting this nonsense?