Being highly-divisible, is what makes Bitcoin completely unique from Fiat.
Divisibility doesn't matter a lot, in comparison with fiat. It might do comparably with gold, but not with fiat; there are quadrillion of fiat cents as well.
The problem with mass adoption is not the supply, but rather governments becoming an obstacle against the cryptocurrency.
Pretty much that. The governments' loss is more intense than the citizens' benefit from switching to a Bitcoin standard (or just from expanding the adoption). If there was a big need for bitcoin, it'd have already been adopted globally. However, adoption increases by the years, which seems to me that the benefit is becoming more and more apparent.