I don't think there's any question that if the only thing we do to increase the supply of great coders is to increase immigration quotas, then this basically just amounts to a pyramid scheme to further enrich the silicon valley elites at the expense of the public. But pg never says that this is the only thing we should do, he only says that it's one of the things we should do.

I don't necessarily agree with pg's realpolitik view of reality, but I also think a lot of the criticism of this piece is based on things that just aren't there.