That the tech has evolved to be better actually is an assumption. The novel data problem hasn’t been meaningfully addressed really at all so mostly we assume that progress has been made… but it’s not meaningful progress. The promises being made for future capability is mostly pretty stale hype that hasn’t changed year to year with a lot of the targets remaining unchanged. We are getting more data on where specifically and how it’s failing, which is something, but overall it appears to be a plateau of non-linear progress with different updates being sometimes less safe than newer ones.
That actually safe self driving cars might be decades away however is antithetical to the hype run marketing campaigns that are working overtime to put up smoke and mirrors around the issue.
Simple - one must strive not simply to be A shit but to be THE shit - The plutonic ideal of shit, the perfect shit from which all other shits are derivitive. Anything less is a failure. So following this logic.
“You ain’t shit” = You are invalid from the rubric, so below par as not to be mentionable.
“You are shit” = Acknowledgement that you are shit of average or middling status but with the implications that vast improvement is nessisary because you are still a failure.
“You are not the shit” = More directed pointed reminder that you are far below the goal of being THE shit and maybe are overestimating yourself.