I haven't read the article, but I would assume any mention of 'bags of water' would be a reference to a Star Trek: The Next Generation episode. Specifically, the episode where the crew of the Enterprise encounters a silicon-based life form capable of communication with humans. Humans are three quarters water, so the silicon lifeforms (rightly?) refer to the humans as 'ugly bags of mostly water'.

To put this into context, it's not uncommon to have the set of people who use and work with technology overlap with the set of people who are sci-fi fans. This is prevalent enough that the culture itself overlaps. Here, I would guess a non-sequitur referring to 'bags of water' is a form of signalling; 'I'm one of you', or something to that effect.

I would go so far to say that knowledge of certain sci-fi tropes, plot lines, and even quotes is a requirement for working on certain teams. At the very least, active displays of ignorance of sci-fi culture should be avoided.

But then again, I haven't read the article linked to by the OP. It's just a guess.

Sometimes I hide things in my posts that I hope someone will find amusing or interesting. Some are obvious. Others? Not so much.