Price of Btc is keep going down.
which one do u choose?
BTC or ETH for ICO?

[/pre]
It's really possible maybe after 3 years or even 5 years and right now it is hard to say because bitcoin is still the most popular coin in the market so that's a good factor in cryptocurrency and because of that the potential is good.
I agree that it's hard to continue being numbered # 1 to 5 years, I'm sure that before 3 years bitcoin will drop and be replaced with better coins, and for now the strongest candidate of bitcoin substitute is Ethereum.