The whole article reads that they're getting more recruiters than they want/need - so, it's a buyers market, and they believe that they can be picky about recruiters, and if some of the most hustling recruiters will think that they're not inviting to work with - excellent, mission accomplished.
But it's not a buyers market, right now. That would imply that there's a ton more technical talent than there are jobs. It's the reverse. It's a sellers market, whether your a candidate, represented by an agency, or whatever....(at least here in U.S., maybe the U.K. is different?)
There's a lack of technical talent, but there's an overabundance of eager middlemen/recruiters - and even if you desperately want talent, you really don't need (or want) all the world's recruiters shoveling shit towards your HR, it won't help you in getting more (or better) talent.
Recruiters aren't 'exclusive agents' like for, maybe, star athletes. Blacklisting a specific aggressive recruiter doesn't mean that you're blacklisting a part of your target employees - actually the good employees also want to avoid the same scummy recruiters, so it even helps.
I agree that it's the reverse if you look at candidates as the "seller". If you look at the recruiters as "sellers", then there are way too many useless recruiters out there. I think they look at the second.
