Because they want to prevent this situation exactly. You either have to ban Wikipedia in its entirety or let everything be uncensored and anonymous. In theory

Because they want to prevent this situation exactly. You either have to ban Wikipedia in its entirety or let everything be uncensored and anonymous. In theory there is nothing stopping them from making their own version of Wikipedia. By scraping all the content from the original. But that's a lot of work compared to adding a web page to a block list.