I've been on the receiving end of Gitlab's calculator. The pay cut isn't small at all; I was offered less than half the equivalent SF salary. And I live in North America, just not in SF.
I guess I just find it a bit weird that your value to the company is so dependent on location that it can vary from 100% down to ~20% of the base SF salary. People living in SF _chose_ to live there despite the absurd rents, and it's not like that changes anything for a remote company.