I could be wrong, but it would be likely Solana or Avalanche would end up taking the place of Ethereum as the backbone of Defi and decentralized operations in the market. Those two ecosystems are wat faster and cheaper than Ethereum and their market capitalization is considerably high (not as high as Ethereum, though).

Ethereum classic would have null chances to do a comeback, due to how outdated it is when compared to what Ethereum currently is.

Just my opinion.