I think tech companies just like to cluster. Future CEOs move to San Francisco so they can run into the next Elon Musk in a coffee shop and start a company together. Why was the next Elon Musk there? because that's where the venture capitalists are. Why are the venture capitalists there? you get the idea..
Its become a big issue here in Sydney. The government brings in migrants to keep the economy growing, even when there isn't the money to build more roads, hire more buss drivers, etc. The only people who score are the house owners who sell for 10x to an apartment developer, who sells the apartments to investors who rent them out to hard working, broke people like myowntrueself