It is indeed difficult to tell in advance (and sometimes after the fact) which of his ideas are sensible and which are nonsense.

Recall that while he managed to hire the right people to get reusable rockets cheap enough for Starlink, it was also the case that in 2016 he said that SpaceX was aiming to use the 2018 Mars launch window for what is now Starship, and also that some time around 2018 it would be possible to summon your Tesla car from the other side of the country and it would find its way to you autonomously and only stop for charging.