I would consider it extremely obscure overall. A large majority of programmers would not be aware of its existence. At the same time there are clearly much less popular languages with articles so it is kindof weird to push to delete. (eg: random scheme implementation w/ no releases in 20 years https://en.wikipedia.org/wiki/SISC) I would say that wikipedia broadly favors programming languages as far as notability. Like most nerd/geek things their footprint skews toward the internet, and people who enjoy geek stuff are more likely to be wikipedia admins than the general population.
This is an argument for deleting those non-notable articles as well, not retaining other non-notable articles.
SISC is there because it's not notable, so the busybodies haven't even noticed the page exists. Odin, however, is notable, and that put it on their radar as a target for attacking its notability.
Unfortunately what makes a programming language famous is usually not the thing that makes it useful.
For example, Go got famous because of how much they pushed channels and launching thousands of green threads per app as the next big thing.
Over time, people kind of soured on these ideas, but Go was a great, simple language with good DX that built static executables.
As a contrast, languages like Kotlin or Swift also brought huge DX improvements to their respective audiences, but didn't really have any standout (novel or divisive) features that made people talk about them.
Odin's like that - it's basically C (or more accurately Pascal) with better generics and some gamedev related features, so it's not as painful to write as plain C.