Mandarin has even less morphology than English[1], so to some extent, working on Mandarin would not "fix" some of the issues of NLP models often performing poor

Mandarin has even less morphology than English[1], so to some extent, working on Mandarin would not "fix" some of the issues of NLP models often performing poorly on morphology-rich languages. But it's possible that focusing more on Mandarin would still lead to improvements in other areas, because the two languages are otherwise quite different (I wonder how well speech recognition works for tonal languages, for example?). [1] Possibly not without reason: there is some indication that languages spoken by a large number of speakers tend to become structurally simpler, while very small isolated languages can often develop surprising complexity.