Biden essentially blamed them too during his recent White House speech
Trump's barely coherent babbling was an insult to the Syrian Kurds that had no purpose but to save face.
Keep in mind the Syrian Kurds are probably our best allies in the ME, with the possibly exception of the Israelis. And the Kurds are, as warriors, about as far as you can get from the Afghan regular army and police. They fight ferociously. They have no natural allies in the region, only lethal enemies. They have no nation, so a lot of them wear the American flag into battle.
Trump yanked support with no warning and left them to be killed by the Turks. No thanks, no attempt at evac, no thought toward organized retreat or security. Just insults.
Biden fucked up, but at least our military is scrambling to evac as many of our allies as possible. Trump would have pulled out just as recklessly as he did before, but Stephen Miller made it clear that Trump wouldn't even try to evac our Afghan allies.
Sorry for the rant. I'm pissed at everyone right now.