I know there are several companies offering anonymous hosting and most of those I would not trust to do even regular hoosting.

Running an anonymous website is difficult. Running an anonymous website is difficult, where users are allowed to upload content that is posted on the site is even more difficult.

Do you do anything to monetize the site? That would be impossible, I think.

I would think a static site (just local html , imagesand as litle javascript as possible wuold be good.

Then finding a hosting enentity of some form outside of US / EU juristrition. Paying in cash without ever meeting. (Cash is harder to trace than bitcoin) (Depending on handover).

and ensure that the hosting provider flushes all logs every 5 mins or so.

Stragenluy I htink part of the package would be to flush teh site in a second if it became needed