That side of the business was a java shop, and had just got 70% through a very long and expensive migration from some old CRM, payment and auth system, to a new CRM payment and auth system. (something like 70 people for four years, lots of design by the CV, Cassandra, and other silly design choices.)
Two devs knew how to use Elixir, they bust out a service, everyone says "Ooo well done" flung it over the fence and leave. Noone else can really support it because they are almost all junior java devs. The other departments can't support it because A) everything was custom, B) only one other person in the entire company (300 devs) knew elixir. Total defecation show.
So when you see people do something because another company said so, politely tell them to reconsider.
to translate into a different context:
Project is to build a grain silo. four teams: One team makes the walls, one the roof, one the vent system and finally the floor.
Roof team decide to use wood, because they've not tried that before, and it looks good. They are all metal workers. They quickly realise the mig welders do not perform as well as they do on steel.
Wall team are using corigated galvanised steel and bolts. Start building the walls, are blocked by both the roof team re-skilling and the floor team.
Vent team decide to use the same, but don't want to use imperial bolts.
Floor team have decided after an away day, that they don't like the current range of ground anchors, so they have decided to spend six months designing a new fixture out of carbon fibre.
To tie it back to the article.
There is no possible way to prove the argument with one company, you need a double blind.