Hi, clarify that I am not a support member or work for itch, just like you I am a user. What I have seen is not a problem of language or the quality of your images.
There are games with pages in Spanish and they appear listed. There are games with really bad quality and they also appear listed.
The topic of NSFW content was talked about a lot a few months ago, no change in policies has been officially announced, however many games with NSFW content have been affected.
There is no official clarification, but the most plausible hypothesis is that certain content is considered unsuitable by the payment companies that Itch uses and that has led itch to take some measures, however Itch has not blocked any games, apparently It is more of a matter of not violating Itch's normal rules, but it puts Itch's relationship with Paypal or Payoneer at risk.
Regarding your question, I wouldn't know what to tell you, in theory it is supposed to be a game and not a developer that is considered when indexing the content.
If you've had problems with other users, it could be that someone complained about your content and that led to it being removed, and since Itch lacks the staff necessary to manually review each case, they have simply passed on, believing that you violate some rule. But I emphasize, this is simply speculation.
EDIT:
The percentage thing doesn't make much sense. It is enough to demand a minimum. In addition, many games that did give a percentage to Itch were affected.
The problem goes that every paid game, it is placed in the crosshairs of Paypal or Payoneer and apparently Itch is not going to put its hands to the fire for anyone, especially if that development goes from paying something to Itch.
Imagine that a friend sells something illegal (in this case, not following the rules of paypal or payoneer), but you receive the payment and then you must give all the money to that friend.
You accept the risk, but you gain nothing. What would you do?