Dreams have been getting a lot of attention as people have managed to create some pretty interesting games and levels in Dreamverse but there are also a lot of characters and IPs that do not belong to Sony.
One such character that we have been seeing a lot is Mario and it looks like Nintendo is not too happy that Mario is appearing so much in the game and have objected to the use of Mario. This has resulted in Piece of Craft, the creator of such levels to removed them from Dreams.
However, as of now, a few other levels with Mario in it are still available including Super Mario Infinity. Of course, creators have been warned from the start that if they use copyrighted materials, their creation could be removed so this is nothing too surprising here.