To a person who isn't using Erlang or ASP.net, suggesting that we should use either of those language packages and it will solve any of our problems without creating a thousand new ones sounds equally non-starterish to me.
To add a counter-example, I have lots of Ruby experience and I've just joined a Go team. I won't tell them to use Ruby, I will just do it where it makes sense and saves us time. (And then we'll have two problems... enter "limiting blast radius")
Point of my counter-example is, I'm extremely skeptical that all the world's problems can be solved by adopting a new mono-culture, whatever it is. There are 100% always gonna be some problems that are better solved in a different language. PHP is the best way to run Wordpress, for example (ok, so it's the only way to run Wordpress, but you get the idea... "Wordpress is the best way to..."), but I've been in high-functioning IT organizations that won't touch that with a ten foot pole, because "it's another language to support, and PHP is icky."
We also got rid of a perfectly fine Wiki in favor of centralized Knowledge-base software for similar reason. "Better to just have one KB. We don't need to be hosting another thing." So the chances of moving everything over to BEAM VM are next to nil, unless you are a product-focused company with just one product, or happen to have an absolute champion leading the effort to migrate all the things. For all the other things, you need to have a consistent answer too.
No tool is one-size-fits-all. Where Kubernetes shines most is under any environment that isn't running a single monolith or building a software monoculture and/or can't manage that for whatever reason (because those are all basic use cases that are frankly easy enough to manage without adding on top the additional complexity of Kubernetes; don't need it, don't use it!) IMHO, diversity in infrastructure is a plus though, and Kubernetes is a technology that it turns out enables this.