Thanks for posting @omshah. I was also a part of this assessment group, in my day job I work on antarctica.gov.au, and several other large Processwire sites.
What are the impacts of having it enabled by default? Is it just extra overhead?
Certainly agree that permissions changes should be logged somewhere for accountability purposes. Not sure if it should be a new log, or part of the session log? Maybe different is best.
Upon reflection, I think you're right here @teppo - I think 429 is best returned for legitimate (authenticated) responses to something like an API to indicate that whilst successful and allowed, the rate limit has been exceeded. It is best to hide the fact any security actions have occurred.
Overall Processwire is so solid, I've used it for over 12 sites now. Everything from small business to large government entities - it's such a blast to work with.