People want to have their cake and eat it too. Silicon Valley companies pay very well because cost of living is very high in the area and they _need_ to pay well to attract talent in that area. If remote work becomes the norm, pay will start to even out across the country. If you live in a place that didn't pay well before, you'll be better off, but if you live in a high cost of work area, you'll probably be worse off. It's just an inevitable truth of how the market functions.... maybe your company says they'll keep salaries the same no matter where you work, but let's see how that plays out in ten years from now.
To that end, 2 days a week in office seems like a great compromise. Personally, I wouldn't want a long commute to work, so I'd pay a lot to be near my office if I'm going in 5 days a week, but for 2 days a week, I'd have much less problem with say a 1 to 1.5 hour-each-way commute, which drastically opens up options for where I can live. And by requiring people to live in the area, these companies will still need to pay competitive salaries for that area, so this seems like a pretty good compromise.