Very recently, it seems History.SE has blacklisted using CJK Unified Ideographs. That is, no Chinese, Japanese, or Korean characters. I noticed this as I tried to cite a Japanese source to answer a question, and it wouldn't let me citing illegal characters.
I think I am just about the only one who makes use of these characters, and given the small currency of china, korea and japan the impact is definitely not big either way. However, what does the rest of the community think?
Do we think this blacklisting is desirable? What are the upsides and downsides?