Because a lot of talent was in office and when a majority of your team is in office and a small minority remote, that remote minority has no chance of catching up to the productivity of in-person team. Be it SV vs Atlanta or SV vs Budapest. I saw that first hand in my 15+ years in this industry.

But with WFH, it is an even playing field. As long as everyone is in a similar timezone and logging in from their home and collaborating via Zoom or Slack, productivity differential vanishes. Why do you think you are seeing a sudden flood of biggish companies going fully remote now?