I think the parent was assuming "steep learning curve" here was qualified as "for a piece of software used by programmers"; while the people that downvoted them assume "steep learning curve" here was qualified as "for a game." It is certainly easy to learn compared to a code-base; it is certainly hard to learn compared to Bejeweled.

Mind you, compared to other “programming games” like e.g. Shenzhen I/O, the main gameplay loop of Factorio is quite a bit simpler to wrap your head around. It's only when you try to ultra-optimize everything that it reaches that level of complexity. (Or when you "program in Factorio", ala "programming in Minecraft.")

> I think the parent was assuming "steep learning curve" here was qualified as "for a piece of software used by programmers";

No. For example, my cousin plays it, someone who typically plays games like the Sims (and other games popular amongst women), has no university degree. She has no trouble with Factorio. I am honestly confused how anyone would call Factorio a difficult game. It's nigh impossible to lose unless you change the default settings to generate a more difficult world with much more aggressive biters. It's a building game, not a shooter that requires any kind of skill or specialised software that requires a manual.

Edit: asked said cousin whether she thought it has a steep learning curve. Answer was "lol, yes! And the curve just continues, there is still lots I could do better". I suppose having nearly only programmers as friends skewed my view of how many people had no trouble getting into it.