array languages are used by several companies for their work. K for example is pretty popular in fintech. Some present companies provide services for array languages as well.
I don't remember twitter having a serious vibe. It's a mess of vibes. Tumblr is also a big mess, but more on the goofy side. I don't think it would change much even with a twitter diaspora.
> One misconception is that languages like J are in the same caliber as less practical languages (esoteric languages like brainf*k) that use symbols more than words. The assumption is that these are mostly for recreational programming.
Making some crude assumptions here, I believe you've already invested a lot of time into studying python, or some other well known language. Understanding python or C gives you an idea of hundreds of other languages because they use similar keywords and structures to represent their code. English also helps a great deal in understanding these languages.
Now, looking at this, giving a language like APL or J a chance means that you have to spend time learning their kind of notation. If you spend your time looking at APL without making an effort to understand it, then you cannot be surprised that it looks like regex to you.
https://www.dyalog.com/case-studies/index.htm https://github.com/interregna/arraylanguage-companies