Thanks for bringing up this topic OP! I also agree that most ICO sites are mostly paid of the ICO teams to get a high ranking and the project itself is not rated as such. I recommend to use these platform only as an overview and don't take there ratings too serious.
Well I use icobench and some other ico rating platforms to do part of my research when I want to invest my money or time. But I don't see them as fool proof. Even the highly rated icos can fail or even scam. Just do additional analysis.
Yes if the ratings are real, but I doubt this. There are so much shady marketing campaigns recently...