I'd argue that Haskell projects are just rare generally, at least partly for the reasons described in the study. It's not debatable that so much of a technology's adoption comes primarily down to network effects, and not a technology's technical merit alone.
Ok. I put to you that if a technology's adoption primarily comes down to network effects, then other languages will also suffer from adoption.
Since 1994:
Java was released in 1995. But this surely won't count because this was funded and shoved down our throats by Sun. Just as C# was funded by Microsoft or Swift and Objective C are funded by Apple
Ruby became a big deal in the web arena thanks to Rails.
Python became bit in sysadmin tools and moved in data analysis (competing with R and Matlab). It's also fairly big in web projects.
Golang became big in sysadmin tools and network applications. It was started by Google but it wasn't really a part of any platform that was being shoved down peoples' throats like Java or .Net.
Erlang became was fundamental to Facebook's first version of their chat, Whatsapp's first version of /their/ chat, Google's first version of //their// chat, Discord's current version of ///their/// chat[1]. RabbitMQ is/was a popular message queue implemented in Erlang.
But where are the Haskell projects?[2] The data suggests there is another variable here.
[1] Discord uses Elixir, but this is built off Erlang's VM so it's Erlang technology. Agree or disagree, I don't think that it detracts from the point.
[2] They are here: https://wiki.haskell.org/Haskell_in_industry
Every time someone posts a message on Facebook it goes through an anti-spam system written in Haskell by way of their `Haxl` monad which automatically batches resource requests, "figures out" what it can fetch concurrently (not really, it's a feature of `Applicative` vs. `Monad`).
People go on and on about how Haskell is niche, but I haven't made a job search in a long time where there weren't more results for Haskell than Erlang, for example. Among the rarer languages it's clearly one of the more popular ones. Yet, here we are, people talking about it as if it's somehow less used in industry than all of the other FP languages.
OCaml is an interesting example. Usually people who haven't used either language outside of a few Sundays here and there will talk about how OCaml is more practical than Haskell and is the more obvious choice for industry... But on just indeed.com as an example it currently has 63 listings with the top ones being for developers in other languages. Haskell has 479 (again it's popular to search for Scala developers by saying they ought to know Haskell).
Everything you have said is nonsense.
Why would anyone trust "random programmers" to some of their most critical business efforts?
For the purposes of discussing the technical merits between different technology alternatives, we must assume some baseline competency of programmers. Otherwise the point becomes "technology doesn't matter because programmers are all stupid", which is not a constructive discussion.
So in context, you could read my post as saying that run-of-the-mill companies don't know how to hire good Haskell programmers.
> For the purposes of discussing the technical merits between different technology alternatives, we must assume some baseline competency of programmers.
No. If it's harder to find good Haskell programmers than it is to find good Python programmers, that absolutely has to be figured in. It's not a technical merit of Python or a technical flaw of Haskell, but it certainly has to be factored into the decision of which to use.
Perhaps the summary would be "Technical merit doesn't matter if all the good programmers for that language are unavailable."
Then there's the problem that, even though we have a good track record of hiring good C++, Java, and Objective C programmers, I am not sure that we would be competent at selecting good Haskell programmers, even if they were available.
So if I'm the CTO of RandomCo, I probably don't use Haskell for that new project, no matter how technically good the language is, because I can't identify, locate, and hire good people for the team. And bad people for the team can turn Haskell into... something less.
It’s the same as when DHH was asked about hiring Ruby developers a little over ten years ago. The question was “why would I use Ruby when there are far fewer developers that know it? Why not just use PHP since there are thousands of PHP developers available?”
The answer being “how many developers do you need? Thousands? Probably not. You probably need two or three.”
I did a hiring round for Haskellers recently for my startup, and we were spoiled for choice. There are so many brilliant people available, and we can’t hire them all.