ICO really have a lot of flaws for IEO, I still haven't really seen many ico projects at the moment, since many people have lost faith in it, rising ico is not correct
For now it is clear that ICO are no longer trusted by everyone, but in the past everyone has certainly been interested in ICO projects even though they did not develop properly in the end, so that's why IEO emerged and replaced all the shortcomings that had existed in ICO.