Z-index warfare is so stupid (the practice, not the name). It's not only with media publications, but ecommerce sites as well.
There have been countless businesses that have lost out on my money because I clicked on their ad (good job!), start reading the product info on their website as it loads (that's basically a sale), and then the page finished loading with a barrage of popups for cookie consent, newsletter signup for a discount code, special offers, special sale, spin the wheel for a prize, etc. That's when I close the tab and forget about it.
While I don't agree with the OP about type systems, I understand what they mean about erlang. When an erlang node joins a cluster, it can't make any assumptions about the other nodes, because there is no guarantee that the other nodes are running the same code. That's perfectly fine in erlang, and the language is written in a way that makes that situation possible to deal with (using pattern matching).
Jai, odin and zig's creators are all part of the handmade network, a community of programmers. You are vastly underestimating blow's reach/influence.
Odin's creator has credited Jai as an influence. You can see him in the comments of old jai youtube videos (videos that go into a lot of depth about the language design). Odin's syntax and features are very similar to Jai, the influence is pretty clear. Odin has other influences of course but you could say it's "jai but open source".
Lastly, jai is not open source but it doesn't mean it's not available. You can message blow to get access to it. Many programmers have used it. There are third party jai libraries on github.