It's really hard for Ada to replace ETH within 1-2 years because the ecosystem on ETH network is too big right now. With a huge number of supporters, Dapps, Apps joined the ETH networks, the network become too strong to be replace in short time. Look at BSC, the network become really popular recently, but not much projects move theirs products to BSC 100%. They keep using between ETH and BSC network with give more profit to developers. So ADA need really long time, much more effort, much more projects to become the next ETH.