Boeing batteries are overheating. Tesla batteries are not overheating. There are sufficiently similar requirements on their performance and safety that any layman can conclude there is something wrong with Boeings design.
The problem here is that the engineers at Boeing are not clowns.
The problem here is that you think that is what is being alleged. It isn't: an enormous and old company like Boeing can have an entrenched culture that leads to decisions being made that do not follow the advice of the engineers. What makes Tesla and SpaceX competitive is not their technical knowledge: it's the fact that they can use that knowledge effectively.
NASA's engineers aren't clowns either, yet their shuttles exploded, unnecessarily. The Feynman committee tore their procedures, not their engineering ability, to shreds.
NASA's engineers aren't clowns either, yet their shuttles exploded, unnecessarily. The Feynman committee tore their procedures, not their engineering ability, to shreds.