You assume it is as effective as onsite work, just like that? If that was the case, why haven't remote work companies trounced on site work companies en masse?
We're not debating the efficacy of the practice, but whether or not it can help prevent rising costs of living caused by tech agglomeration. Certainly "taking remote work more seriously" would include investing in pilot programs, experiments, and innovating processes/technologies to make it better and better. And it's something that large megacorps could work with, if they cared about rising CoL.