I was looking at ETH and as far as I understand, this coin is mainly successful because of the ICO's nowadays.
ICO's are booming and it looks like it never ends. But what if all ideas are gone and the amount of new coins which use/ need ETH are decreasing. Would this have much effect on the price?
Maybe someone can correct me if I am wrong?
Indeed! Eth is successful because some ICO's use Etherium to host their project. The demand for eth just keeps getting higher and higher as more ICO's are om trend right now.