But hey, I'm sure it's "different" this time, right? You're right and everyone in the crypto space is wrong.
But they weren't wrong. Geocities and Pets.com died without making very much money.
The giants of the Internet were Search Engines, Online Shopping, Video Sharing, and Social Networks. The giants of "Blockchain" probably either in awful, primodial form (ie: Pets.com was online shopping, but a terrible experience. Geocities was also a social network... albeit a bad one by today's standards).
So today's coins probably will fail to some new coin made 3 or 4 years from now which really figures out the "killer app" of Blockchain.
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I think its fair to say that "Blockchain" as a technology will exist in the future. Back in the 90s, one could reasonably expect that "Jerry and David's Guide to the World Wide Web" was going to be the primary methodology of looking for new websites... before the Search Engine was perfected.
So many people lost their life savings chasing after fad technologies of the 90s, Webvan being one of the most notable. Billions of dollars invested and lost into just... awful ideas that no one understood.
Frankly, the neckbeards of the 80s were right. The vast majority of 90s webpages were utter crap without a business model.
For example, how many would have predicted the rise of small, fairly low-tech, text search ads as the multi-billion dollar revenue linchpin for all global search.
Similarly, whatever the core long-term value of crypto-currencies will be, it probably hasn't been truly understood yet.
Most of these ICOs are similar to the period before the dotcom crash when simply adding .com to the name of a failing business was enough to lift it's stock value. Anyone else remember that or can give an example?
Whatever rises from the rubble of this cryptocurrency bubble bursting is what will no doubt be most interesting and what will no doubt end up being truly world changing.
Looking forward to the middle/end-game.