Secondly, large corporations seem to function via rules that are completely immune to reality. Every 10 years or so Intel will not only insist everyone is in the office, but will look at relocating teams into their head offices for any given project - literally giving the people the option "Hey! I hear Gdansk is lovely this time of year". This sort of organisational bullshit from large companies isn't going to go away. However, you can look at the opposite side, I know people (not engineers) who work at companies where they hot-desk every day and the office is only provisioned for 70% of staff to turn up on any given day because they're too cheap to actually provide everyone a desk.
I guess what I'm saying with that second point is that for most large businesses these choices are going to be more about corporate bullshit than some sudden epiphany that working from home is great.