The sad (or wonderful) fact is that anyone can write a new programming language now; I could for example use Claude create a wrapper on top of an existing languge (for example, a Python-like syntax wrapper for Scheme) in a few hours and start marketing it as a new language. So how can Wikipedia tell toy languages from real ones with actual useful adoption?

It's simple; get coverage in reliable sources,[0] and the article can come back. That really doesn't seem to be too high a bar to cross.

[0] https://en.wikipedia.org/wiki/Wikipedia:Reliable_sources