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 think your opinion is optimistic and no evidence about it. Although the market cap of XRP is higher than ETH, I believe it is only temporary because the potential of ETH was always better than XRP, and the price of XRP will never surpass ETH.
In conclusion, I think the future, BTC, and ETH still dominate the cryptocurrency market and all altcoins price will depend on the rate of ETH and BTC.