Factorio is amazing and the way it makes you remap certain parts of your brain works differently depending on the person, and the paths they took in the game, so it is a little hard to describe.
Based on how other people try to explain it, I'd say the closest comparison matches the experience of being a "traditional" programmer being exposed to haskell.
You've kind of just got to play it to experience it yourself.
There's two parts to factorio:
1. You have to figure out what the next goal you need to focus on is, and then work backwards through the steps you'd need to achieve to get there.
2. You need to wrap your head around the task at hand figuring out how to build pipelined systems in a limited space. You might think you need A which can be turned into B which can be turned into C, which is correct. But it turns out the next step you planned requires some of your C to be turned into D while still making C, then you need to combine come D with B to make E, but suddenly you're not getting enough C to make D because you're using too much of the B to make E. You can swap some of the things that turns A into B to make B at a faster rate, but the A to B thing takes up more physical space, so now you need to move the things around in space without ending up getting tangled.
Repeat these two things in a loop for the basic game loop, then add in the occasional emergencies that you didn't foresee that can wildly change your current objective.
The difficulty curve in the game is designed in such a way to always let you figure out what your next objective is, but without you knowing all the pieces to get there.
And there are multiple paths to the end so you need to figure out how you're getting there.
Plus each of the ways you can use to get to the end work in different ways, sometimes subtle, sometimes utterly different.
Because Factorio is always training your brain in different ways, you'll find that you're way of problem solving has become better every 10 hours or so. You'll randomly get ideas out of the game of how to improve things or do things in a different way and you can try them out whenever you get back to the game.
Even when you finish it, you can go back and retry it to see just how much you've retrained your brain. You might even want to try the different paths to brain train other methods.
You can finish the game for the first time in about 50 hours. Depending on how much you game, this may be a lot, or hardly anything, but I'll point out that it's not one of those repetitive daily-mission grind-fest second job games. It's much more like reading a really good book series that you're enjoying.
