It's not about the office, it's about the commuting, which can often increase the length of the working day by 25% or more, and can add a thoroughly miserable start and end to that day (stuck in traffic, or on delayed/overcrowded trains), and make life seem much worse even if you're doing enjoyable work with great people in a really nice office.

Offices have their pros and cons (WFH can be a horribly lonely experience for anyone who lives alone, for example). But it's removing the commuting that makes WFH such a massive win for most people. And a big win for the environment (which should be reason enough to try and keep it going)