Investors are not tired of ICOs per say, they are just tired of getting scammed by these fake projects, and losing their money. It has become quite a big risk to want to invest in ICOs these days, and this is very bad, Before now, ICO investment used to be a very good option for investors, but with the many scams all around, one has to be really careful.
Yes, the main problem with ICO is the problem of fraud among these companies. It should be urgently resolved by the state filter for fraudsters. However, this seems to be not so fast in time. States are not in a hurry, as if they want citizens to be convinced of a large percentage of cryptocurrency fraud in order to discredit the very idea of cryptocurrency.
The second problem common for this year is the fall in the cryptocurrency market. The period of stagnation affects both the activity of investors and the activity of ICO.