So you have not suffered any losses from a call center and are not getting collection calls? If a collector violates the FDCPA you are entitled to the greater of up to $1,000 in statutory damages for each violation or your actual damages, plus attorney's fees. If these are not calls by collectors then under state law tort law you'd be entitled to just whatever your actual damages are assuming you can prove negligence.
You seem to be assuming that all banks operate the same way. They do not. They don't all use outside call centers and when they do not all those third party call centers operate the same way. It is not the case that all of them will tell you that they are bank employees rather than agents for the bank, for example.
Feel free to complain to the CFPB and FTC about your complaints about how you think banks utilize call centers. But I'm not seeing any basis for a class action here from what you've described so far.