When the geography of labour ceases to be an important part of production, attempts to keep foreign workers out of a country become counterproductive. Workers who stay remote will be subject to remote expenses. If those are lower, it’s harder to compete.
Say the cost of living in San Francisco is 100 and the cost of living in Prague is 50. You can thus pay a remote worker living in the latter city 70 and he will have as much disposable income as a local worker in the former earning 120 (both will have 20 in disposable income).
This is much lower than importing labour to San Francisco and “underpaying” them. Say you do that and only pay them a disposable sum of 10. Your labour cost is thus still 110. Not much of a comparable saving to that of going remote.
So if you’re a local worker, would you rather compete against imported labour that undercuts your rate by 10 or a remote worker that undercuts it by 50? That depends on the efficiency of that remote worker, of course. If being remote means they can only do half as good a job, no problem. If they do 90% as good of a job, big problem.
Another angle: What if you pay both the local and the remote workers the same, say, 120? In Prague, that would mean you can attract the same quality of talent that it would cost you 170 to attract in San Francisco (holding all other things equal, for the sake of argument).
As the world gets better at remote collaboration, this is only going to get worse—or better, depending on your perspective. Up until recent history, protectionists have been able to claim that having someone in a remote location is simply too inefficient. So the argument could stay about the process. (Pair programming and other co-location techniques are great fodder for these kinds of arguments).
When the process becomes a minor issue, it’ll have to become about the people, if you want to stay a protectionist. That is the claims will have to be about how the remote workers are worse workers. Not as smart, not as easy to talk to, not as proficient. I reckon those arguments are not going to have a long term future.
Likewise, I reckon that fighting to keep local supply of skilled labour down in areas of work that can be done remotely also does not have a long term future.