The dominance of San Francisco is mind blowing and flies in the face of the narrative of "decentralizing tech" that I have been hearing over the last decade
Because they're accessible, and remove the burdens/predatory behavior typically associated with relocating to high cost-of-living areas.
More importantly, it speaks wonders about the culture. If a company can be successful without everyone sitting in a single office, it really speaks to their collaboration and communication abilities, which is harder to gauge out of the gate with a traditional co.
Though I would point out that because remote is a "new" style of work, it's probably too early in remote work's history to use this as evidence of remote work's unsuitability in general. This being because there are likely a number of "tricks" to making remote employment work properly that today's remote companies haven't yet mastered, while in contrast physical companies have a significant and long cultural history to pull the best ideas from.
TL;DR: yes, but I think remote work is also at Semver 0.X.Y right now so we should give it some time to grow