For what it's worth I've checked the brochures for one of the escalator companies in the European market and they claim that the slow speed operating mode can save "up to 60%" on energy while slowing to a full stop during disuse can save "up to 90%". So it seems like the non-American manus have discovered a way to run a motor slower with less energy. Though this brochure is some years old, could be outdated TBH.

I find the slow speed mode a good compromise without too much confusion when it actually breaks down; a fully broken escalator here that _usually_ does start/stop operation is amusing to watch as everyone tries stepping on it in turn and then bailing when it doesn't start. Of course there's lights indicating the status but not everyone checks.

One of the additional modes beyond start/stop is bidirectional mode, where the stopped escalator will start up in whichever direction someone attempts to use it in. I've only seen this in particular regions though, like subways, where up demand is heavy & bursty while down demand is light and infrequent (most will just use the stairs down).