well for people who enjoy those work itself, it's essentially living a fantasy where you actually get rewards for doing a good job.

I can't tell you exactly what it is, but simulation games are nearly always satisfying for me

Probably because it's a sped up, consequence free, approximation of the real thing, without any of the entry cost but with a similar satisfaction for succeeding

And like, it's not like other mechanically complex games are really that different. All a game is, aside from the story and art part of it, is problem solving and surpassing obstacles