A bad market is a bad bad market, and it definitely must have an effect in prices of coins, though it may not be the only reason why a lot of projects aren't succeeding, but it is one major reason, although some projects, very few actually manage to thrive under the conditions, but those are the best of the rest.
If the market were to be good, so many failed projects would probably have been selling far above their ico price, but thats at the moment a distant reality for them
Many projects at this time fail, failure can occur during the project is underway because the revenue target is not reached or after the project is completed where the expected price of the coin does not get a market response, so the price is very cheap.
In addition, many speculative ICO organizers, pursuing short-term things, such as cheating, and are many who are pessimistic about the current crypto project.