I was surprised to see in a HN comment the explanation that not everyone finds Factorio enthralling.
The gameplay experience is so similar to what many developers do in their dayjobs, that this leads to one of two responses: "...and I am not constrained/bound, it's so fun!" or "...but with Factorio, I get no tangible output from putting in effort."
I work in ops and a side of programming, have some related hobbies and that's exactly my feelings about Zachtronics games. "Why play some virtual computer emulating game where I have a dev board with actual computer to program"
But it hasn't happened with Factorio. It just have that perfect blend of everything that I don't mind it being basically what I do for my day job.
The gameplay experience is so similar to what many developers do in their dayjobs, that this leads to one of two responses: "...and I am not constrained/bound, it's so fun!" or "...but with Factorio, I get no tangible output from putting in effort."