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
You have a valid point. However, those scammers took advantage of ICO's anonymity specially during its height in 2017. Projects pop like mushrooms, everyday you will see them popping around and victimising investors. And this continues up to 2018. So that by 2019, we haven't seen any legit project took off and became successful before scammers have ruined the reputation already.
And then when the new business model of IEO/STO slowly making its ground on the ecosystem, ICO became dead and experience dry spell as investors shift their attention to the last business model of IEO who in turn are very lucrative for early investors or those who have a lot of spare money to throw on IEO projects.