Why should he take a pay cut? His employer no longer has to spend money for his use of office space. The costs associated with having an office have been externalized onto the employee. If anything, he should be paid more for saving his employer those costs.
Should has nothing to do with it. Jobs that have non-monetary benefits, all other things held equal, have lower market clearing rates of pay. That could be job security, working with famous people, prestige, or in this case geographic flexibility.
People just like those things, or at least enough do. There are lots of lawyers that want to wear a black robe, get called “your honor”, make decisions, being deferred to, and so on. So even though judges don’t make much money, comparatively speaking, there’s no shortage of people that want the job.
My last 3 remote gigs (2 of which were pre-covid) have all been at higher rates (over each other, and over prior on-site work). The 'you have to take less for remote' thing is by no means universal...
No, because that ignores the savings the employer receives for not having to hotel the employee. But employees stioo have to ensure their working space. So remote==cheaper is not guaranteed.
Why does that matter? You said the employer shouldn’t care what the employee does with their money. In that case, so too the employee shouldn’t care what the employer does with its money. Under that logic all that matters is the market clearing rate—-not savings or extra costs for either the employee or employer.