Do you think Cardano will replace Ethereum?
Personally, I think that both blockchains will develop in different directions in the future.
Both blockchains would therefore be relevant and coexist.
I personally think of something like this:
Ethereum = DeFi
Cardano = dApp
I also thought of something like this:
Ethereum = NFT & Gaming
Cardano = dApp & DeFi
I don't think that Cardano (ADA) can replaced Ethereum in the foreseeable future due to iris very low acceptability in the market. Its network is not simple and user friendly and no significant project launched on its network that could have impressed the wide majority of crypto community. In contrast Ethereum is well established and recognized network with Billions of dollars invested on its protocols.