Joseph: Elevators have motion sensors so that the doors will no close of people. It would be against civil law to have an escalator that is prone to crushing people. There are doors that re-open when they hit someone, perhaps all Shabbos elevators have these. Normal ones would not, so I don’t see how some people hold that it’s muttar to use a regular elevator when a goy presses the buttons.
DY: I did not know that about the programming of Shabbos elevators. I guess they must go slightly slower when they have weight in them if they don’t use more energy. Still, that makes me question even more how people are okay with the goy-button-pressing. I agree with the train analogy. I was never disagreeing with you about escalators being assur, I was more arguing that we should be questioning elevators more; sometimes my analogies end up coming across reversed.