All of these poor souls were perfectly capable of setting up 'bobsdiyproject.org' and attempting to get popular support. Individuals trying to do this would have fixed up-front costs for developing all the 'little' stuff that KS does, zero access to an existing base of people interesting in paying, and no access to mainstream media to promote their idea.
The curation aspect is a large part of what creates value in KickStarter. The notion of 'SelfStarter' proposed in the blog completely misses the benefits to the community provided by centralised screening. If any and all projects were approved it would be chock full of scammers and opportunists with poor ideas - the SNR would be so low as to drive interest away.
Would I pay 5% of all cash raised specifically from HN members donating through a 6-week link to my project with no money upfront? Yes, absolutely. Zero-risk, $0 down traffic which only pays out if you hit your own projected goals?
Is Etsy a scam? Is eBay a scam? I'd say KickStarter has more favourable terms than these (still valuable) sites as they require money upfront regardless of the success of your listing.