It can hurt to swallow a lot of the BS, but you can fight the good fight inside these companies, one guerrilla incursion at a time. Some of use do still exist in management, or at least believe we still hold true to the conceptual integrity of what agile means vs. what it has become.

You only get to execute the nuclear option once (i.e. quit) so yes you need to understand where the line is, but there's almost always a better option.