I personally can't say give an assurance to that, but as far as I can tell, few IEO are doing good so I would say that we could see it last longer than expected. Although some exchanges have not been doing good or have been involved in scam activities, that could be a challenge in the future
we've seen ICO at the peak of success, many ICO projects have managed to get enormous funds and many projects can develop. now of course we want to see where the IEO also gets a place in its success. it will make growth in the crypto market. the more successful the project, the greater the adoption with fresh money will enter the market.