That's not impossible, if the Ethereum did not fixed its issue it might happen. We all know that if the price of Ethereum rises or the chain is crowded we all know how ridiculous the price gets. It is only one of the things the Ethereum needs to fix but it's really not impossible that Ethereum can be overthrow by other coins.
I just see a high percentage that they will completely overcome the cost of the network as well as the time to transfer the tokens, recent hard fork in london and a few plans with updated codes that i don't remember the names of but claim their progress is going to reduce competition from other projects. Even in case this plan is postponed and canceled, Cardano cannot take away the users here, quite a lot of stronger projects will take over these important folders, the small ant won't be able to cause too much pain and death