There are some people who aggressively reject reasoned argument as to why it is a con. Sure, these people are in for an awakening.
But probably many of the backers do not have English as a first language, are taken in by glossy photos of what appears (and is intended to appear) to be a real product and can't really follow the, admittedly technical, proof as to how it can't be real. Do they deserve to be decieved?
Probably some of the backers are vulnerable people. Low mental ability, over trusting personalities etc. The web page is very specifically set up to give the impression that they are buying a real product - apart from a tiny legal disclaimer, quickly clicked away. Do they deserve to be decieved?
Probably many of the backers belive that Indiegogo gives some (any) protection from complete fraud on their site, and that even if it turns out to be a fraud that they have some channel, any channel, to get their money back. Do they deserve to be decieved?
Is it right that Indiegogo should facilitate, profit from and protect pre-meditated deception, whatever happens to the backers?