Currently, the entity usage tracking service knows two cases for label usage:
- the label in the wiki's content language (aspect "L")
- a label in some other language (aspect "X", which covers all other aspects)
On a multilingual site like Wikimedia Commons, pages often use labels in multiple languages. Any such languages would be tracked as using the "X" aspect of the item, triggering a purge whenever any part of the entity is edited. This is particularly bad for entities that are used on hundreds of thousands of pages, e.g. countries.
Solution, as per discussion T90563 (updated March 18): Use per-language aspects. Instead of the "L" aspect, use "L/en" for the label in English, "L/ru" for the label in Russian, etc. Implementation is tracked in T92288, deployment is tracked in T92988.