That's because investors lost their trust in ICO regardless of how good some of the ICO, they shifted their money and attention to IEO obviously for fast profit and safe investment, which ICO have losses, last year and this year, and next we will see fewer ICO.
Yeah it's natural because every time the trend must change, despite the many ICO scams that make many investors deterred.
but it won't make the ICO disappear, the project will continue to come but not as much as before