VCs have the resources and capacity to pursue due diligence, even in very technical domains. Indeed this occasionally fails and you get Theranos. Yet for the "public", Theranos will undoubtedly become the norm.
VCs don't necessarily do rigorous due diligence, especially at the early stages (where ICO's typically play). That being said, VC's typically do some soft diligence checks that investors of ICO wouldn't normally do, for example: personal check backgrounds within their own network, personnel reference checks, review potentially proprietary/confidential information, etc. So it's not necessarily that they have monetary resources to expend during the transaction process, but rather informal/trusted resources at their expense.
It's unlikely that VCs have more resources then the collective internet though. Of course there will be scams, but there are scams with or without VCs.
The question is -- should only VCs have the opportunity?
My understanding is that, taking cryptocurrency as an example, crowds of uninformed investors will stampede on something that's popular rather than something that's necessarily an objectively good investment. Regardless of your thoughts on cryptocurrency as a concept, I would say an intelligent investor would balk at the kind of ICOs and prices we're seeing.
A lot of this, I think, can be explained by simple psychological concepts like repetitive attraction (seeing something in the news again and again makes you more comfortable with it), good first-impression traits (GOOGL performing better because it's more pronounceable than TWTQR), and other things that have been fuxing with the stock market for decades.
The market has never been rational, and as I've learned from crowd-funding campaigns, the internet didn't make that situation any more rational.
