Big exchanges, especially those in favour of the US, is dangling the Flux and Ergo carrot at this time. I don't know why miners want to migrate to ETC... if Ethash is the prerogative, there are better Ethash derivatives like QuarkChain, but I guess the existing adoption of ETC is more lucrative. Anything can happen after the merge, perhaps some ETH funds flow to ADA, FTM or KDA, etc. Don't know it is all dark. A lot of funds will be in limbo with ETH 2.0 staking.