Lots of interesting posts on this thread. I work from home most of the time anyway, and in fact left a job a couple of years ago because the boss wouldn't let me do more than one day a week at home even though the clients didn't care where I was as long as they got their work done on time and to the standard they expected.
If people can't get through to customer service teams etc, that has nothing to do with WFH and everything to do with inefficient systems. I ordered a new broadband connection during the later stage of lockdown and spoke to people working from home who answered the phone and got things done. Nothing to do with WFH and everything to do with training and attitude, I'd say. I ordered a book from a charity and was told it might take a while to come because people were WFH and not in the office to send them out, but in the end I think I only waited about 3 days for it.
I am in my late 40s but still have nearly 20 years to go before retirement age so I don't think I am sitting pretty and being selfish "at the end of my career". I could have, and have worked from home for years. It might affect your promotion prospects if you are not in the office, but does that matter if you are happy with what you do?
I do think it could be an issue for staff starting out, either young and new to working generally, or new to the organisation. There are currently have two new members of staff in the team I work in, one new to the organisation, one new to the team, so we'll see how it works out.
But I certainly don't intend to ever go back to a full time commute, spending £££s and time just to work somewhere else, when I can work at home or in a local hot desking hub very well. Or even my local library, for free.
As for the "is everyone using Zoom question", I use Zoom, Teams, and bluejeans. DH uses Teams and Webex.