If she actually thought that was tantamount to "you'll never work in this town again", she needs a reality check. Oh, this one recruiter firm won't work with me, whatever will I do?
I've worked at four different companies. In order, I got those jobs through Craigslist (2007), Monster (2012), Indeed (2014), and a friend referral (2016). None of them involved recruiters. Also, during the times I've been looking, I talked to a very large number of recruiters. If one of them blackballed me, it wouldn't affect me because I talked to so many other recruiting firms, and even then I ended up getting all my jobs without them.
It's a threat that is totally unrealistic.
As a recruiter, I'd actually say that technologists are more likely to be able to damage a recruiter's career than the other way around. If word gets out about a recruiter not behaving properly, that word can travel much faster in the worker space than word travels in the recruiter space.
I can see where the arguments about trust etc are coming from (not that I necessarily agree), but that one I don't get at all.