Yeah, trends tend to cycle on here. It also depends on the general fandom mood and what prompts are being posted. Like how recently there've been a lot of Kylux prompts, and before that there were quite a few prompts heavily featuring 'background' characters like Mitaka and Thanisson. Prompt more of what you would like to see, and you'll most likely see other people thinking about your prompt and coming up with their own variation. :)