People love San Francisco - the culture, the energy, the people, the beauty, the opportunity, the freedom, the openness - that's why the cost of living is so high there. The more who leave, the more affordable it is for entrepreneurs and other dreamers who want to do something wonderful. I want to live someplace filled with those people; I want to meet them at the cafe and in my workplace.
Cities have been the great engines of modern culture and economies for awhile now. Nothing has changed. Coronavirus is a brief interruption. Remove work doesn't change it - Covid didn't teach SV about remote work (many SV companies tried large-scale remote work several years ago, then brought many back to the office). There's a reason businesses try to create great office environments - dynamic, exciting, fun, social - it's highly creative and productive. Now you think people will be just as creative and productive sitting by themselves at their desk at home?
Taxes are a major part of that - taxes are how we invest in our communities. To treat them only as an expense is ignorant, sometimes willfully so. California and the Bay Area have been taxing and investing for generations, and look what it turned out. The infrastructure of the Bay Area, U CA Berkley, and Stanford (which at least receives research money and massive tax benefits in tax breaks, I assume) are just three examples. The Golden Gate Bridge is another. Next time you are in a city, look around at all the things that the people got together, democratically, and built, funded, and operate. I believe in democracy, a fundamentally American belief.
In the end, it's a reactionary political statement. The reactionaries have been targeting cities for many years because they are powerbases for Democrats, progressives, are populated by many non-white people, and they are cultural threats (merely by the fact of their existence and success: their diversity and integration, their cultural leadership, and in business and economics: what great, innovative industry comes from reactionary parts of the country?). You'll note who made the big statements about leaving - Thiel and Musk, possibly the leading reactionaries in SV.
Reactionary politics is fundamentally corrupt - a lie about the world, in every aspect, to protect and accumulate their own power and assets. They're right - they don't fit well in SV. Reactionary is anti-progress, anti-optimism, it's anti-. SV is doing well if the reactionaries don't stay and stagnate, but leave and create more space and opportunity for the newcomers, the next generation. I believe in those newcomers much more than in Thiel and Musk.