Elon Musk says more people need to come to work in San Francisco or the city will struggle to survive

• Elon Musk is encouraging workers to move to San Francisco to help the city survive its doom loop. 
• The billionaire said Twitter's headquarters will remain in San Francisco. 
• Other major tech firms including Meta, Snap, and Salesforce have reduced office space in the city. 

Elon Musk is encouraging people to move to San Francisco and work there, saying the "city can't survive" unless it overcomes the urban doom loop.