If you leave out 2020, JDs last 3 seasons with Boston were .937, .867, .790. Not horrible but very trending the wrong way, and at age 35, I can see not relying on them to reverse. Turner want noticeably better, but at least had the option of playing the field.
It’s not a slight at JD that I don’t mind him moving on. But he really didn’t do much his last few seasons in Boston to make re-signing him a no-brainer..