Because "Office Vacancy Rate in San Francisco Just Hit a New High", That means property owners aren't making money. Workers aren't out spending to come in, stay and leave. All that is taxable, which is why government officials want people back in the office. In every city, the downtown core's tax revenue subsidizes the suburban sprawl all around it. Good overview of the research on this: https://www.youtube.com/watch?v=7Nw6qyyrTeI