Agreed. We have them in Paris at a minority of stations. Hopefully this will eventually be ubiquitous and not having them, like elevators with no internal doors

Agreed. We have them in Paris at a minority of stations. Hopefully this will eventually be ubiquitous and not having them, like elevators with no internal doors, will seem extremely outdated. (Yes, this must be costly, but it's not just relevant to prevent suicides. I have once been at the very brink of a subway platform in Paris without that did not have such equipment, along with a huge crowd of other people who were eager to get in the train. Anyone behind could just push anybody on the (electrified) tracks, and if panic were to break out for any reason it would have been a disaster.)