They're TECHNICALLY still up there for political/budget reasons. If they wanted to buy a new capsule to go get them, we could.
But on the same note, ALL of the astronauts are "stuck" up there for budget/political reasons. We're not going to bring them up and down willy-nilly cause it's way too expensive. They should have come back months ago, but since they're original capsule was decided to be too risky, they pushed it back to the next available SpaceX capsule.
Elon is both arguing for an INCREASE in funding to go get them now (which is far too late, we wouldn't be able to safely prep and send a mission to get them back sooner), but also DECREASE funding for the ISS. Just whatever gets him attention and more numbers in his Forbes ranking.
Starship Troopers had the highest survival rate, so that one.
Absolutely not The Thing because you have no idea if escaping means the end of the world. You'd have to murder suicide the whole place.
Aliens... Maybe. It's survivable, but just barely. You'd probably want to hold a live grenade with the pin pulled the whole time, so you'd at least never have to be brought back to the queen.