These arguments could use a little more precision/evidence and some concrete examples.

>1. Array languages aren't well suited to every problem.

No language is suited to every problem?

>2. They are ridiculously capable for many types of problem.

Irrelevant? It only matters if it is more capable than other languages.

>3. The people using array languages are generally insanely smart.

Folklore. Impossible to quantify. Most of all, there are really smart people using all languages.

>4. Learning how array languages work is a steep challenge.

This is not persuasive.

>5. It’s awesomely mind expanding.

Like philosophy and psychedelics? People care about GTD.

Seriously, I’m listening. What’s the real competitive, objective, case for k?