They seem biased to me. A friend of mine who's doing an ICO told me that they paid 10ETH for 5 quality ratings and that's that! I noticed that some ICOs with good project, team, and good social media presence are struggling with getting good reviews.
With all that said, should it still be a factor to look at when investing in ICO?
If you are referring to the reliability of the ICO rating platform, I guess you are right about the biased thing but we have to consider that not all rating sites can be bought. It is our duty to identify which is more reliable than the other. ICO ratings are some kind of publicity and exposure like reviews. Good or bad, still a publicity so we have to consider that investors look after for those ICO that are well-known and have the greater probability to be successful.