Most of the ICOs are just scams and repetitive. There is no reason to collect user's money in projects like these. User's got bored of this and eventually lost interest in investing. This is how the ICO market fell.
Except that the ico market *hasn't* exactly fallen yet. There are still a lot of projects coming out with stolen whitepapers, fake identities of team members, and bounties that don't pay or that require participants to do kyc right at the end. As soon as I stop seeing those scam accusation threads I'll be convinced that ico's are dead.
Already started there is no bright spot that will arise in an ICO so it's time to go and find other ways to make coins that can make you a millionaire.
Good luck becoming a millionaire in crypto now. It was possible back in 2009-10 and maybe even up to 2015 if you had enough investment capital and had the foresight to hold bitcoin through 2017, but now everyone knows about bitcoin and I seriously doubt there's going to be growth like there was in the early days.