It looks like you are only counting for the scam project but you are not aware if there was a lot of successful icos.
It's better for you to visit this site
https://icodrops.com/ and look at the previous ico list and there was a bunch of successful icos. The future is still really bright.
based on the data from this site it can be seen that the relevance of the ICO has decreased significantly compared to 2016-2017, people’s opinion is interesting whether anyone is following the ICO, or many have switched to IEO ?
Possibly yes, since IEOs are raising funds if the projects gets launched on reputed exchange but most of the investors moved to existing coins since they lose all their capital amount when they invest their money on new projects so people prefer investing on coins with highmarket cap value.