First, bad driving should never be condoned on a automotive enthusiast site.
Second, if the OP checked his right side mirror, he would know how far away the car was, and would not have said he didn't know. If I had to guess, I'd say if he checked his right side mirror, he would not have been pulled over.
Third, if the OP checked his mirrors, he probably would not have gotten pulled over.
Fourth, just because he didn't kill someone today, doesn't mean he's not a serious threat to others.
Fifth, you cannot judge distances or even grossly approximate them using the cameras Tesla installed aft. Don't take my word for it. Test it yourself.
Six, my anger is at all the Tesla 'drivers' who encourage his driving style, not just him.
The AP/FSD/NoA system is the best compromise at our level of tech today. But it is far from safe unless used by an attentive driver. Which the OP admits he's not one of, yet he uses the system anyways.