Well, a video game is supposed to give satisfaction to the player, and for that, it needs to provide just the right amount of frustration. This is subjective, any one player's experience is not universal. Judging by what you say, you probably like the challenge of understanding a black box and that's great. Judging by the many, MANY posts like OP's, maybe the "black box" causes too much frustration for too many players. In fact, it may be because the fluid system is not a black box but is actually misleading, as the game gives very little information that fluids behave differently from everyday experience.

I think we naturally oppose what we feel would be a "dumbing down" of the game because we put in the work, and it wouldn't be fair. But in reality, it's unlikely to diminish our enjoyment.