Push back by saying "No, you find me valuable at this rate, and that doesn't depend on where I live since I'm remote already". You may even have to find another remote job.

Typically, even for the most valuable engineers, the company will just say “see ya” at that point.

Finding another remote job with acceptable pay / benefits / work responsibilities / etc., is very hard and takes a long time.

Honestly, I think you’d have to get another job offer (either also remote or in the location you want) to use as leverage for your existing employer to let you move without decreasing your pay.

I just think almost every employer would force a pay decrease in that case, no matter how unfair or unrelated to your value-add, and unless you already had another offer lined up, you’d never be in a position to give them an ultimatum in which you’ll quit if they decrease your pay.

It’s why this idea of earning a SF or NYC salary while living in some nice Midwestern suburb is still nearly 100% myth.

Huh. I guess I'm a myth then.