I upvoted you because it's a good point, but consider it was the first launch ever of this rocket so presumably people were reluctant to put important and expensive payloads on it.
Wouldn't that be heavier by volume, have less mechanical resiliency by volume (no internal rigidity), and have more complicated physics (free flowing, capable of convection/rotation)? Maybe a big block of water ice... but honesty, seems to to have pretty limited utility. If long distance space exploration relies on lifting water vs harvesting it, then it's kind of a nonstarter?
