I did search for "trivial sorting network", but the only networks that were called trivial were the ones for exactly two elements, while this algorithm sorts an arbitrary number of elements.

Could you link to what you're talking about? And what's its big-O runtime?

This is a much stronger result from the 80s: https://www.researchgate.net/publication/221590321_An_On_log...

There is discussion about Sorting Networks in the old post (find link in one of the top comments of this post)