Earlier quoted context omitted.
They largely won't unless forced to. Management in the UK by and large sucks.
I always wonder how people come up with these statements, is it just anecdotal? To add my own, my company was shifting to working remotely for the development team gradually, but now our CEO has been impressed with how well we adapted to working from home and has told us that our office will not be open until September at the earliest.
Sure it might just be cleaning/utility costs/stationary for now, but longer term expansion won't have stepped accommodation costs. And if locations can be done away with ...
I can't see why workers would be happy without higher wages? I want at least to afford a house big enough to have an office space (I'm working out of my bedroom, my line-manager is in their kids bedroom, their line-manager is in a utility room (storage and laundry room)). 5-10% increase in wages should do it.