Well I don't think that could technically be considered a race condition, as it's clearly a design problem in the code causing what would appear to be a "pseudo" race condition.

Why not? It is a race condition, just like TOCTTOU is a race condition that doesn't necessarily involve threads.

Note the difference between race conditions in general and data races that involve unsynchronized access to shared memory.

And “Javascript would have categorically improved on this compared to more traditional multi-threaded solutions” remains true nevertheless.