Well, in the case of Kurds, you'll have to mention a specific group because we don't ally with ethnicities, and as far as I know we still support many of our Kurdish allies.

In the case of Afghans, they're not our enemies - however, they largely decided not to fight an invading Taliban army. So it seems like allowing the Taliban to take over is actually how we supported them in what they want. As it turns out, the country wasn't willing to fight the Taliban, and America is more than willing to let them do that so long as we don't think it will lead to more attacks on America. They'll have to live with the results, not much we can do about it.