True early stage investors focus on technology, team, demos, prototypes, and so on. Probably team more than anything else.
I don't think that's true anymore, if you want to get the best valuation/terms for your company you can't go into a meeting with a potential seed/early stage investor without showing some kind of traction.
The bar has been set higher for startups, that is why there is this downward movement in the VC food chain to focus on early stage deals, they are seeing companies with traction and revenue, so they want in earlier before it's too late.
Sure you might be able to raise money just based off of technology, team, demos, prototypes, and so on, but as Jason Calacanis puts it, it's just table stakes: http://calacanis.com/2015/11/02/dont-bring-a-knife-to-a-gun-...
(I no longer work at YC, so I'm just speaking to my time working with 10 batches there.)
Angel investors, seed funds and accelerators are one thing - they are an element of the start-up eco-system. Until quite recently this was a very small niche, and VC has existed for at least 2-3x as long. (And that's just how we now know it, funding for risky ventures is centuries, if not millennia old)
The article describes an independent "Micro VC" fund with partners and LPs, but another type would be small corporate funds. I worked at Bloomberg Ventures when it was just starting to figure itself out (now known as Bloomberg Beta) - perfect example of a relatively "small", corporate-backed entity that you could also describe as a "Micro VC".
And it's the emergence of these funds, this article highlighting the non-corporate funded ones, that is a noteworthy phenomenon.