Well, you are ignoring the point. The whole differentiating strategy between Tesla and everyone else is the incrementally improvement of large amounts of vehicles versus the magic “hey, we came out of nowhere and now just drive ourselves”. This has been repeated though out tech history and the incrementally improving real life one always wins.

The large number of vehicles makes it harder because you can't do hardware upgrades and a regression will kill someone.

And Tesla will just ingest large amounts of data from their fleet and magically dump an L5 solution one day? That's believable?

Elon Musk has been promising imminent L5 self driving every year for the past 7 years; that requires more than incremental improvement. The ones actually doing incremental improvements are companies like Cruise and Waymo, making it work one geography at a time.