The main argument that anti-WFH people will use is that without millions of office workers commuting to work, the millions of other people whose industries rely on that commute will lose their jobs. In essence, without the meaningless business instigated by a commuting workforce, people doing meaningless jobs wouldn't be able to make a living. But this brings up an interesting question: why do they need to work at all? If you think about it, they don't. At the moment, millions of people spend their day working in service of millions of commuters, even though there's a perfectly good alternative. The commuters pay for no good reason and the commuter-dependent workers work for no reason. The only people who truly benefit from this system are the commuter-dependent employers, who get both money and labor (the employers of commuters also benefit, but for different reasons unrelated to this post). But what if we both kept WFH and let these people be paid their wages without working? The loss of their labor wouldn't be a loss at all because it was an aspect of an pointless system that we wouldn't be within and no one would be losing any money because the money which was being needlessly given to them would keep going to them without change. Commuters get to WFH, commuter-dependent workers don't have to work unnecessary jobs, and everyone benefits (except employers)!
P.S. One other nice bonus of this would be that GDP would no longer be used as a determinant of economic health, since this positive change would almost certainly decimate it, proving its problematical nature.