Backpage is on point as well as the overall point is the same, you cant be liable for crimes related to the inital crime if its not actually a crime. Ie if the gains are not ilgotten, you can't be tried for laundering them.
If you follow the DMCA (e.g., honor takedown notices, register an agent if you’re a platform, and act quickly when notified), your exposure to criminal liability is essentially zero.