Now is the moment when the hype around the projects disappeared and only enthusiasts decide to invest or participate in the bounty.
Or in another words when it is "blood on the pages" of the forum is'n it? Aposteriori we can assume that spring-summer of 2018 was the end of ICO in their current appearance. And a scheme was as old as a world itself. Now public cry for "decentralization" changed to "we need regulation" (and profits as with Ethereum I suppose

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No specific time for that but I'm still hoping that it will started to end the hype for the purpose of now which it getting profit, most of the time not to fall crypto because its worth living with crypto.