You provided a conjecture based on incomplete data as fact, he stated that it's conjecture until additional data to support it is there... the burden in this situation is not on him.
> You provided a conjecture based on incomplete data as fact,
No, I never said it is a fact, it is, as you pointed, a conjecture, and I provided a source (ok, wikipedia) for the amount of water in the universe
If you or him knows of a reason for why the most common elements in the universe that combine easily wouldn't result in an abundance of their combination I'm all ears.
(Which doesn't mean the amount of water is going to be near the amount of H2 or just the amount of Hydrogen present in the stars)