At some point the US will leave and the Taliban will return, no one has any plan that has realistic chance to prevent it. It sucks, but sending American soldiers to die in there is not gonna change it. Seriously, people having dying there for years because no president want the fall of Saigon pictures on their watch and kinda hope the next one deal with that mess. Imagine dying for that goal.
"Don't want to screw over the Kurds" is not a policy, and not a good enough reason to support another Bolton open ended illegal mid-east adventure.
Also, I never got the sense that Democratic voters cared all that much about the Kurds before Trump said he's withdrawing troops (and every pro-war talking head started talking about how awful is the withdrawl from Syria), I would imagine most of them wouldn't have even known about that mission (I know I forgot about it) which further support my theory that this is first and foremost about instinctively assuming that Trump is wrong about everything, which again, not a terrible assumption, just one that I think happened to be wrong on this one case.