The advice in PBP is designed to be one fairly good way to do things. It is not the only possible one, and it is not necessarily the best for all circumstances.

I agree that if you attempt to use exceptions as a flow of control, then it is much better to throw objects than strings. But I'd prefer that exceptions generally be fatal, and would like to discourage trying to use the exception system for complex flow of control. Which means that all of TheDamian's arguments for exception objects are arguments for how to better do what I'd like people not to do.

This is not to say that PBP is wrong. It is correct that it provides an internally consistent set of best practices. But it is not the only possible one, and it is not my preferred one.