Because that still means you have to live near where you work and that gives you a small home (at least if you live in a large metro area) due to the real estate being scarce and expensive.
But having 2 people work from home increases your required footprint and yet you live in the same area as before. If i need an additional 20sqm in or near London, that is going to be expensive.
True, but if you're only travelling one day a week you could probably stomach a longer commute on that one day than if you were doing it 5 days a week. I guess ideally there would be some variety in the way jobs offer home working, then people could choose for themselves and hopefully that would take some pressure off housing markets in metro areas as well as giving a sense of connection to employees/employers who particularly desire that.
My official office (which I rarely go into) is about a 30 minute drive away. But to your point, we have another office in the city. It's not really that big a deal for me to take commuter rail in now and then (or drive in early). But it's still about 90 minutes each way.
OK for a day or so a week. But that's a huge chunk out of your day if it's a daily thing.
True, but this also prevents the problem of (or worry of) excessive outsourcing. The company I work for has been actively trying to outsource my department's jobs for coming on two years now, with quite a few vendors, moving about 20 percent of us to managerial positions but the work quality is not of a high enough standard. So with that and the time difference, I'm not overly concerned, but this would at least put away such concerns. Plus, as noted above, there is something to be said from some face to face interaction.
But having 2 people work from home increases your required footprint and yet you live in the same area as before. If i need an additional 20sqm in or near London, that is going to be expensive.