The push for working from home is just two other things that have become taboo to debate and is manifesting through the work from home "movement", which is the loss of private offices, and the debate about reducing hours of work.
And if people are allowed to work from home, they have an alternative that fills the loss of the private office, and they can also take upon themselves to shorten their working hours to something more "reasonable".
There are other factors (why waste fuel/accident risk on commutes, easier to cook healthy lunches, et cetera), but those are the biggest ones for sure. It would be nice if we could have the hours debate out loud and for real.
And if people are allowed to work from home, they have an alternative that fills the loss of the private office, and they can also take upon themselves to shorten their working hours to something more "reasonable".