[sillysaurus3]

No no, I'd never claim something as foolish as FP is inherently less productive. It's the opposite in my experience. Once you have a bunch of libraries and utility functions that you know how to use, you'll wipe the floor with any stateful programmer. The hard part is getting to that point. I'll elaborate more in an edit when I'm home in like 30 minutes.

EDIT: Maybe a little longer.

[sillysaurus3]

I'm short on time, but my main point was just that if you're already a stateful programmer, it's difficult to become productive when switching to functional programming due to a combination of factors. FP isn't inherently more difficult than stateful programming. It's simply that stateful programmers have already spent the time to become productive, whereas switching to FP requires another time investment in terms of learning a new mindset, getting a programming environment set up, learning how to exploit the environment (how to be "fiercely effective"), learning which libraries to use and how to find them and set them up, and most importantly: deployment. Deploying native apps in stateful languages has seemed easier for some reason, whether it's python or C or whatever else. I tried to use lisp for gamedev, but it became a nightmare to figure out how to actually deploy everything including libraries along with all dependencies. The end result of deployment needs to be a program that's launchable by double clicking on an icon, which seemed difficult. (Again, my info is out of date, so maybe things are much better now.)

So it's just a combination of mindset change plus a different "context" for programmers to get used to. That, along with deployment problems and sometimes lack of documentation, leads to a lack of incentive for anyone to make the switch. Since stateful is more popular, it's almost always better for productivity to start and stay a stateful programmer. However, for personal skill level, everyone needs to become a functional programmer for at least several months and try to develop production apps with it. Who knows, you'll probably get much further than I did, and figure out a way to convince all your friends to make the switch too.