Can you prove your wordings or have you any link which says like this? Never spread rumor as many altcoins already proved their value and established and investors first choice. May be some altcoins do scam after their ICO but not all altcoins are scam.
Here is the link to an interview he did yesterday where he clearly states they are all scams or 99.5% of them
https://www.youtube.com/watch?v=gsaSVf5YxfI