> As the employees start to have families, they most likely move to the south bay for better or for worse, and I have a hard time imagine that they'd enjoy commuting via BART or Caltrain for more than an hour every day.
The 25-35 crowd are probably the worst employees that Twitter can ask for; too experienced to "keep their head down" and too young to suffer from ageism and be tied down with families. For companies like Google and Twitter that traditionally lean left and encourage employees to speak up, moving the company headquarters is probably the easiest way to filter out activist employees (since these days the company is making a hard pivot to a privately held conservative operating model).
The 25-35 crowd are probably the worst employees that Twitter can ask for; too experienced to "keep their head down" and too young to suffer from ageism and be tied down with families. For companies like Google and Twitter that traditionally lean left and encourage employees to speak up, moving the company headquarters is probably the easiest way to filter out activist employees (since these days the company is making a hard pivot to a privately held conservative operating model).