Martyn, I personally think it’s a good idea to invent common names in order to make nature more accessible to laypeople. But beetles are hyper-diverse, so it’s not easy to come up with millions of distinct names!
If we look at the Curator Guide for taxonomic authorities:
We don’t get a definitive answer! The linked forum post is https://forum.inaturalist.org/t/taxonomic-resources-for-insects-wiki/, which also doesn’t provide the answer!
To be fair, the “Leaf Beetle” part of the name gets across the idea that it is a Chrysomelid, which is a good entry point, in my opinion.