A lot of companies aren't even making knowing their core language as a hiring requirement.
You could make an argument about Elm's community size for long term support of libraries. But hiring isn't a very good one. Elm isn't entirely fringe nor immature.
And I'm not debating what's possible technically, but if it was a wise business decision by the customer to choose Elm. Based on the popularity in Norway in 2017, today and what it likely will be in the future, I think they should have made a different choice.
You say 'here', so I'm going to assume you mean that literally, and that you are indeed in Norway. Forgive me for assuming the worst, but you seem to have an axe to grind against either Elm, Vy, Bekk, or something else based on your several posts on the story—is that correct?
The article, and others have pointed out, it appears to be a good business decision, as far as hiring is concerned. They haven't had issues with newcomers learning the language. The OP them self said that Elm was a selling point for working there.
As someone who recently lived in Norway, and who has used Elm professionally there, we've also found it to be a good business decision.
A lot of companies hire for 'polyglots' these days anyway. For the most part, I wouldn't want to hire someone who wouldn't be capable of picking up Elm to a decent level, relatively quickly. When mentioning that we used Elm, it usually elicited excitement.
It is more a concern regarding how the tax I'm paying is used. I understand that people are happy with Elm today. But how will it be in 5 years? Given the small Elm community, will it still be up to date then? Will it be easy to recruit then?
I know of other publicly funded projects in Norway where they ended up using non-mainstream languages, and where it became a problem in the long-term.
Yes, you've asserted that several times here, based on next to no information.
As for recruiting, using Elm has put Vy in the spotlight several times the last years. So even if most people aren't elm developers, I think this has at least given lots of potential candidates a positive view on working there.