(Also, whoishiring already posts 3 threads a month and I'd rather that number go down than up! but my attempt to kill the Freelancer one, or rather to merge it in with the others, met with resistance some years ago)
I think we had a short conversation about this a few months ago. Mostly this is coming out of the success of the "Who's Hiring" model. No sign-ups, no filtering. Contact whoever you'd like to contact.
On a personal note, I've met some of the most talented colleagues I've ever had a chance to work with here on HN.
I wanted to recreate the same opportunities that HN's "Who's Hiring" opened for me but focusing on Co-Founders.
A monthly or at least quarterly thread enables a quick browse of what people are interested in creating. I enjoy the sentence or paragraph cofounder pitches that can be read in seconds instead of going through scores of profiles. I raise my digital pitchfork in support of these threads! 43 votes for this thread in 3 hours, seems others do to.
I'm open to your argument but that particular logic doesn't work because these things always attract different sets of eyeballs, i.e. lots of people know about the one but not the other.