>The amount of lawsuits that these processors get co-named in for providing payment rails is probably enormous
yes, that's called being a billion dollar business. Literally any billion dollar business is facing dozens of lawsuits on the daily. They have dedicated lawyers on hand for this ineviability.
There's a lot that needs to change, but I don't see these businesses bothering. So forgive my lack of sympathy.
What i'm saying is no such protections exist for financial transaction that occur on a network. Infact, the opposite exists, laws exist (called Know Your Customer [4]) that specifically hold financial networks (like Visa and Mastercard) liable for allowing transactions related to fraud, money laundering or other high risk transactions like gambling and adult entertainment.
[1] https://en.wikipedia.org/wiki/Safe_harbor_(law) [2] https://www.congress.gov/bill/109th-congress/senate-bill/397... [3] https://en.wikipedia.org/wiki/Qualified_immunity [4] https://en.wikipedia.org/wiki/Know_your_customer