I never see posts on HN from the perspective of "I'm a technical founder with an idea and a product, and I need a non-technical co-founder who can pitch, market and sell it".
I fall in to this camp, sort of. I'm not looking for a non-tech co-founder, but certainly open to the idea. However, as I meet people, the ones who seem to be capable are generally already doing their own thing. To a large extent, this is probably a similar problem non-tech people face when looking for tech co-founders - the ones who are most likely to be capable are probably already doing something.
I meet a fair number of people who might be non-tech co-founders - they tick some of the boxes. But when discussing things more, then almost inevitably fall short of my own expectations.
This is hard to put in to words, but the ones I've talked to seem more in love with the idea of being in a startup than actually working on one. There's also seemingly little drive to do much more than talk. Generally, also, there's little financial stability in their lives, to be able to deal with no or limited income for several months while ramping up. And based on discussions with some potential co-founders over the past several years, there seems to be little willingness to be at all flexible with their own ideas - they have tended to think of themselves as Steve Jobs, and me more as a Wozniak to be used and thrown out later.
So... again, while I'm open to the idea, I'm not actively looking. Perhaps I should be actively looking, and would weed through the bad fits faster?