Is moving to a global business hub still worth it for a software founder?

The remote-work argument and the location argument are both usually overstated.

You can build software almost anywhere. You cannot reproduce every network everywhere. Certain cities compress meetings, capital, talent and accidental introductions into a small physical radius. That is valuable when those are the constraints on your company.

The useful question is not 'where are startups best?' It is 'what is currently scarce for this company?' If the scarce resource is uninterrupted engineering time, moving may be harmful. If it is enterprise relationships or capital, geography can still have leverage.