> How do you come to such a conclusion when there have been many languages whose success was specifically tied to the fact that they were dynamically typed? Doesn't that indicate a pain point?

The pain point was always tedium, not difficulty. At least that's how it was sold. We haven't seen a new major dynamic language since type inference went mainstream (and existing dynamic languages are putting a lot of effort into enabling static typing), and I don't think that's coincidence.