I used to see C WLs primarily before COVID. The influx of FIFO J WLs had changed the dynamic and I find these FIFO J WLs are a lot more fun and sexually enjoyable then others.

I don't think OP is doing a fair comparison. You are comparing young J WLs with C MIFL of cause you see difference. Obviously you are just more into MIFLs, nothing really to do with ethnicity. If I am have sex with same 20year old C girl and J girl, chances are better experience with J girl

J and C WLs have very different career path. J WLs endeavor their prime age (18-28) in the sex industry, JAV or sex worker. when their pass this age and lose the shininess, typically they are more experienced by then, they retire.

C WLs give their youth to a bunch of "Zhanan" ("Douchebag", "Scumbag" or if anyone has better translation), who will ravage and spoil them until they become broke or in debt, they start sex work to get by and look for an "honest man" to get married.