Investors can not get tired because it's their bread, they are tired of scams and a lot of bad projects, which are even funny to read
You are right, investors who know how to choose projects and get profit from it - they cannot get tired of it, but now it is not related to the fact that many projects are scammers, because fraudsters have always been in this industry. Now there are bad market conditions and they are not favorable for investing in ICO projects.