Maybe related to the super annoying T30441 ? If that's the case, then:
Task 30441 and this task in a nutshell: Cantonese (yue) is treated as a variant of Chinese (zh) because of it's db identifier/subdomain zh-yue

Still not fixed on version 6.7.1.

Yes, we're having a difficult time with sorting through Cantonese as a seperate wiki, vs Cantonese as a "variant" of Chinese as the code would indicate.

This all stems from the long ago decisions about how to support the different character sets for the Chinese language family vs setting up different wikis, particularly before standards existed in this area: https://en.wikipedia.org/wiki/Cantonese_Wikipedia#:~:text=The%20ISO%20code%20for%20Cantonese%20is%20yue.

While we could override the "name" of the Wiki to Cantonese in the display, that may cause more confusion, since its not consistent with the database that drive the Web UI, etc.

We're definitely interested in the best way to solve this, but need more expertise and may be limited by what the platform/history has done upstream.