I don't think that is true at all. Most people can't even get in on the ICOs.
The "whales" are buying ICOs left and right, and dumping their Bitcoin/other altcoins. That's the main reason for ETH's rise.
Eventually some of these ICOs will prove to be scams, or will get hacked with catastrophic results, and ETH's price will fall again. It doesn't necessarily mean it won't rise back-up again, but by then we'll just have to see if ETH is still a top 2 coin to get.
s/some/most/
This seems like a plausible theory to me.