@year_2038 not many . the people known about weibo > twitter > mastodon .
Around 11 instances were registered to IPs in China and (presumably) able to federate past the GFW as I expect the scripts were run from Europe.
may not seem like many but more than in some North European countries!
if you don't read/recognise the language Its easy to overlook Chinese toots and/or conflate them with Japanese (the Chinese often share cat pics on the timelines)..
A Mastodon instance for info/cyber security-minded people.