If I am not mistaken, by the end of 2018 the ICO project has been abandoned by many parties for various reasons that have emerged and turned to the IEO.
In my own opinion there is no difference really about the two as they are still all about crowdfunding. The only edge IEO has over ICO is the fact that there is usually no delay in listing the coin after the IEO on the same exchange.
You might be right on this that there is no difference at all. The success of the project still lies on the team of developers and advisers. So, I think ICOs will still be here together with IEOs.
every projects depend on developers team work.if they could build usefull and adoptable product in crypto market , i am sure they will success in market and crowdfunding.no matter they will use ICO or IEO scheme.