Not surprised he took the money. The trade-off has always been that if he demonstrated superior results, he might get a 4 year deal at a very good price in exchange for not taking the 19MM.
If he was failing as he was doing at Toronto, his value would drop off a cliff and that 19MM would be all that he would get.
But he appears to be fitting in in Sacramento - After joining the Kings, Gay averaged 20.1 points on 48.2 percent shooting
He can take the money & still have a good chance at a very good contract. The SF free agent market is thin enough where he can still command a good price