> The main problem is that category theorists keep writing stuff claiming that, if only you get through the math, you'll eventually be able to apply the category theory to typical everyday programming problems.
There is no "typical everyday programming problems." It's an incredibly broad discipline, and one person's typical is another's esoteric.
When you're designing an API, it's useful to know when you're dealing with one of the common structures that occurs in category theory, and there's a somewhat high cost to missing that, since you can end up with a "broken" feeling API where the pieces don't fit together properly, or where the different parts aren't consistent with one another.
There is no "typical everyday programming problems." It's an incredibly broad discipline, and one person's typical is another's esoteric.
When you're designing an API, it's useful to know when you're dealing with one of the common structures that occurs in category theory, and there's a somewhat high cost to missing that, since you can end up with a "broken" feeling API where the pieces don't fit together properly, or where the different parts aren't consistent with one another.