That is not how marketing works. Show me a reputable book about marketing that says: promise something that doesn't exist.
Anyone who thinks predictions about the future hold the same weight as statements about things that currently exist ought to know better.
The unsettling duality that Tesla fans will accept is that somehow Musk is both an unrivaled genius AND he's consistently betting incorrectly on Tesla's timeline for L5. When other self-driving experts in the field indicate full L5 for the industry is probably a decade or so away (optimistically), I'm not keen to believe that Musk is just blinded by pure optimism for 6 years running.