look this is all very straightforward. this is called hysterical fear. these kids are scared genuinely shitless of trump. but instead of processing that in a productive way they displace it into this delusional thought that somehow replacing biden will save them from their fear.
indeed precisely because it won't happen--it *obviously* is not going to happen that biden steps out--that it becomes the locus of their obsession. they need to fixate on something impossible "that would totally save us all" because then they'll never have to be wrong