The discussion is about issues in the bay area. They contribute a huge amount to the tax base there, so saying they don't pay taxes isn't fruitful to this discussion. If those taxes isn't enough to handle issues in the bay area then bay area taxes should be increased, simple as that. And if that makes tech companies leave the area then those tech companies couldn't afford to operate there, and if they can't afford it then nobody can and everyone would have to leave the area.

Edit: The main point is that nobody can say that San Francisco has less money with those tech companies operating there than they would if those tech companies left. They are among the richest places on earth and should easily be afford any measures that can be afforded anywhere.