On the one hand, I agree with you that there should be no limit on what you can study or research; on the other hand, I agree with Duan that many of the research topics in China are very much just "useless". They neither present important theoretical contributions nor resolve critical practical issues.

I think the question is not whether those odd areas/topics should be researched or not, but rather, whether a reasonable balance and priority in resource allocation between these odd topic and others are established.