Didn't his max contract value go up a lot when he made 3rd team All-NBA this year...and consequently cost Klay Thompson a lot of money?
That said, Jordan would have screwed it up anyway.
His supermax grew, but Jordan could have offered a four or five year deal at the same numbers Kemba got in Boston. Given the fact that Jordan gave an unproven back-up (one playoff run doesn't make you a proven player) about $19M/year, paying Kemba Boston money would have made sense.
We don't know whether Kemba would have taken the extra year at that rate.