Ninety percent is way too high. There may be a lot of low value projects, but it is unlikely that 90 percent are just outright scamming you.
Where are you coming up with such high numbers?
maybe it means better safe than sorry. ofc it's hardly that full 90 % are scams but this number imo includes weak and uncompetitive projects that die fast.
not everything ends with a scam, indeed everyone says 90% of ICO is scam and insecure,
but there is one thing that makes me believe. the 10% ICO is still good