Actually, this was Jimmy G’s move. He saw this opportunity, and agreed to sacrifice his $24 million salary and play for $6.5M this year to avoid a release/trade (possibly to Seahawks). At least for some guys, it’s not all about the money.
...sorta.
Jimmy had conversation with other teams about being backup. Reportedly with the Rams as well.
There are some franchises though that wouldn't have brought him back regardless of his price tag to remove all doubt from their young QB. 49ers took alot of flack for bringing him back.
That's not to slight Jimmy though. I think the 49ers wanted to do this all along (barring a trade offer for sizable return) but never thought it was a real option. Big credit goes to Jimmy on this one for swallowing his pride and taking that backup role and now he's playing for a contender in a contract year. He has everything to gain.