In large part because at least some portion of California lawmakers knows their history well enough to be aware that all of Silicon Valley is a thing in the first place because people were able to leave and take their ideas with them and start something new.

A huge portion of the value of Silicon Valley today can still be traced back to when the “Traitorous Eight” left Shockley Semiconductor to form Fairchild in 1957, and build tech based on what they’d learnt at Shockley, with many of them then going on to leave Fairchild and found further new companies. The outcome of that among many others resulted in both Intel and AMD, and the same pattern has repeated many times.