Neither the Dodgers, Angels and even the Padres this year seem to have any problems attracting and signing free agents. And considering the Giants have won 3 of the last 5 World Series, I think it's fair to say that he's just making excuses. It's not like he hasn't had opportunities to leave and passed on every one of them to stay in the horrible state of CA.
If he really hated the taxes he would have left years ago. Would you like some whine with that cheese?