Anyone familiar with SEO knows the gold rush boom ended abruptly in 2012 with the penguin update. Before that time, making money and ranking websites was incredibly easy and predictable.
SEO is not completely dead even today, even after the penguin update. It is just much more demanding and not so straightforward. It takes real hard work, you have to do intelligent website promotions, and your link building strategy cannot be as direct as it used to be. I fear that today the ICO boom might be coming to an end soon. I'm definitely not talking about blockchain, blockchain will revolutionize our world, I have no doubt about it. But ICOs, that simply use blockchain to raise funds for shady businesses, I believe are starting to dry up. People are starting to cotton on to the shit that they are. The question is, when will it all abruptly end? Any quick way to make money with no substance always ends abruptly at some point.
I agree, it has to end sooner or latter. Just like with SEO, the things will become more complicated, but I believe ICOs will still exist. They will just have to put much more effort, to prove their worth before being able to raise money. 