There are resumes you're going to see today that are a terrible fit, but might be exactly what you're looking for in three years. It matters how you go about rejecting those people. Charity is contagious, so is indifference. Disdain, on the other hand, is virulent.
You don't want people to delight in the prospect of working with one of your competitors. That's far, far worse than just missing out on hiring them and never getting a second shot.
There is also, I think, a false economy in having one person talk to an individual on their own. There is no one to see how that interaction goes. If I were in a protected class, you've also created a liability for yourself by having nobody to corroborate an exchange.
We are trying to make an inherently expensive process cheap and we are breaking everything in the process. We didn't fix deployments by doing fewer of them. Why do we think we're going to fix the onboarding process by avoidance? Finding and training people is part of building a team, which is necessary to build a product. If you have a bunch of people pushing back on the obvious parts, they're probably pushing back on the rest of it too, making little empires for themselves at the expense of their peers, the product, and the company.
We used to use referrals instead of cattle calls to fix this problem, but we don't like the kinds of hiring biases this brings in and so we threw the baby out with the bathwater. Now we have all of the worst, dehumanizing attributes of a lottery system, and not really many benefits from doing so.
Probably what we are all not learning from this decades long experiment is that if you haven't solved your diversity problem before you are famous enough to have an embarrassment of riches in your inbox, then you never will. Everything that comes after is a series of rear-guard actions trying to replace bad decisions with less bad ones, failing as often as succeeding, and justifying your arbitrary decisions as more merciful than the alternative, when in fact you mean more merciful for yourself.
Right now, for instance, I've been keeping my eye on José Valim (Elixir), because I have a suspicion that his team may have cracked that nut already, or soon will.