There’s Churchill. There’s Semmelweis. There’s JFK. There are the pioneers of computing. They have all been ridiculed by many. Luckily for the world, they have also persisted in their folly. And have inspired many others.
Regarding the "marketing hype":
Phrasing it this way, to me, implies that Tesla wasn't really seriously working on the problem. Or that FSD by way of cameras + neural nets was an approach that has already been demonstrated to be a dead end. Both of which I don't think is true.
It's true that Tesla has been promising a coast-to-coast autonomous drive since 2016. They have, as they say themselves, "egg on their face". Also, it's true that one can argue over several of their design decisions. But I think there is a difference between a group of people working towards a hard goal, and a group of people knowingly creating unrealistic expectations for marketing reasons.