Most people ignore these contacts, so it does kinda work to match needy recruiters with underemployed IT pros. But when you're already at FAANG making 400k a year, it can take a recruiter phone call, two tech screens, and an onsite before compensation comes up, and you're now invested like 10 hours into a negotiation where your BATNA exceeds whatever budget they have written down. I've had one recruiter get a bit angry even over it, as if my number was unrealistic (I assume they were unprepared to make a competitive offer).

Since there are so many of these lowball recruiters, some people resort to screening them out up front with a salary negotiation.

If you don't set some kind of expectations with a recruiter then you might end up in processes where the 'negotiation' happens at the back-end, when you've been through the hoops, and the company has no chance in meeting what you're looking for.

This can waste a large amount of your time. Which is probably valuable if this is a situation you're concerned about :-)

It's not so much that as a negotiation technique it's outdated, it's more that you need to pre-select positions in some manner so you don't waste your time. If you are being paid X and a company pays their best employee X/2, but think they are paying 'really well', you're never going to not be wasting your time.

I admit it's not exactly applicable to salary negotiation, but IMO leading with a high number can help cement the counterparty's perception of your value. I think it really depends on what type of company (and what level of its food chain) you're applying for.