Separate fandoms and even separate platforms will have their own trends when it comes to the type of content they create. The above quote compares fanfiction from the same fandom but on different platforms.
A survey of the ‘Sherlock/John’ tag on the MTSlash archive revealed that a majority of the written works were rated ‘G’ or ‘PG’ as opposed to the predominance of ‘M’ and ‘R’ rated works on global archives such as fanfiction.net an AO3.Nivanka Fernando: Media imperialism, fan resistance and state censorship: BBC Sherlock Slash fandom in China https://www.academia.edu/16121021/Media_imperialism_fan_resistance_and_state_censorship_BBC_Sherlock_Slash_fandom_in_China
This observation shows again that when talking about trends in different fandoms, it’s worth to take a look at the different platforms they appear at and if they appear differently there.
Do you have similar observations about different kinds of platforms you are familiar with?