If ICO wasnt been plague by scammers acts ICO will way better than IEO, ICOs are programmed to run on the projects very own website and no any third party involvement at all so any fund raised will go directly to the dev or project team, no loss of funds to scam exchanges,after some successful IEO fund raise on some exchanges they dont bother to send the funds back to the project teams
I think that even now many new projects would gladly carry out the ICO and would not share the collected investments with the exchanges. However, now ICO has lost popularity among investors and new projects without exchanges risk even being left without investments.
In addition, many IEO projects are of little interest in terms of long-term investment, because these are the projects of one day, you bought today, then the exchange propamped the price of the coin, tomorrow you sold it at an increased price and forgot about the existence of such a project.