Let's get obvious joke over now: no, there will not be "pushmen" on platform to squeeze people in. This photo is from 1967—at most, these days in Japan there are attendants who make sure backpacks and purses are safely inside.
Here's more on Tokyo Metro's involvement:
https://londonist.com/london/transport/elizabeth-line-tokyo-metro
I got to ride the Liz Line last summer, and it was pretty sweet. (Bye-bye, overpriced Heathrow Express...) More in this HIGH SPEED dispatch:
@straphanger from what I know of this cultural phenomenon in Japan this is primarily a winter thing when it’s the same amount of people riding, but they have extra bulk due to their winter clothing. I do appreciate them tucking in every last fold of clothing and fabric so the doors don’t pinch them. 
@straphanger Didn't the tax payer pay for most of the build???