Agree. You can of course treat "Boiling water" in its gerund form where it functions as a noun:
"Boiling water should be performed in a metal pot".
> It’s a hazard, a cooking stage, a state of matter
All of these are ancillary and depend on context, but in every one of these downstream cases the same underlying process is happening: the water is boiling.
That's using it as a [verb] [noun], not a gerund. If you are using it as a open compound word (or a gerund) - the "boiling water" IS in a boiling state.
All of these are ancillary and depend on context, but in every one of these downstream cases the same underlying process is happening: the water is boiling.