Very true. It's impossible to not break an API in some cases. The solution described should give developers an easy way to correct design decisions or deprecate

Very true. It's impossible to not break an API in some cases. The solution described should give developers an easy way to correct design decisions or deprecate parts of the API that have changing dependencies. It's more about improving the DX of breaking APIs to improve or evolve them. The case you describe cannot be solved and all affected clients will accept that. I guess if regulators ask for such a big change, there will be enough time for all involved parties to prepare for the change.