as we know now Ripple has taken the position of Ethereum (ranked 2 in the coinmarketcap), and will this change everything in the future? My point is that Ripple replaces Ethereum whether there will be major changes in the future, such as whether all ICOs will use Ripple as a payment from their ICO to replace payments using Ethereum and all exchanges will use Ripple (XRP) as a payment to buy or sell altcoins on the exchange.
if I think that can happen and what do you think? please give your opinion.
I don't think it will be possible. Ethereum the easiest way to payment for ICO's. All project (even based EOS, NEO and others) uses Ethereum. I've participated a ICO. It is normally based on EOS. But they create their first token which based on ETH. Then they Swapped to EOS. So XRP has completely different mission on crypto world. It is competitor of Bitcoin not Ethereum.