UK banks are just as bad. A company I worked for previously gave a bank's investment products a high risk rating because of poor investments/compliance and they sent all sorts of nasty shit out.
Every bank has a "send people nasty shit" department by the looks.
I think the better answer is to not reply at all or ever acknowledge receipt of said 'nasty shit'. Make every step a challenge for the opponent, it's a war of attrition. And never get mad at the lawyer, s/he usually bills by the hour and they are delighted to send out useless letters all day long. Informing the bank that this is a waste of time is bad for job security.
It's perfectly fine to get mad at the lawyer for abusing their skill doing such people-hostile work. They can choose a more honorable line of lawyering.
Telling banks and other financial institutions to fuck off was just an operating cost for the company in question. It was in the budget.
That's how I learned how the finance system worked in the UK. Assholes lobbing grenades at each other whilst the rest of the companies just get on with it.
Every bank has a "send people nasty shit" department by the looks.
The answer is as always: "fuck off".