Agree as well. Just picked up my Model 3 two weeks ago, and love it. But, the blind spot detection is the one item that is clearly inferior to most competition. Unfortunately I don't think it can be completely fixed with existing hardware, but this software update would be very helpful.
I have long legs, so I keep the seat fairly far back - when I adjust the left-hand mirror all the way out, it is still not close to the SAE-recommended angle that would eliminate the blind spot. I'm thinking of sticking on a little convex circle mirror - ugh. Anyone else find a way to improve the left-hand mirror?