Iirc there has been a class action about this. And in just amazingly classic Apple form, they added the ability to see if the device was being throttled... in

Iirc there has been a class action about this. And in just amazingly classic Apple form, they added the ability to see if the device was being throttled... in a point release of the then-current major version of iOS - and did not back-port it to the previous major version. My device wasn’t being throttled. But in order to have the privilege of even CHECKING that fact, I had to upgrade the OS and move my iPhone further towards its obsolescence. (That’s kind of hyperbole... but only in that I personally didn’t upgrade the OS specifically to check whether it was throttling.)