I have no crystal ball but I believe it will take a lot to replace btc. Btc has the name of bitcoin, brand recognition, network effect and first mover advantage as well as the backing of approx half the community. But that’s just my thoughts.
If one of them kills the other off relatively easily and remains king all will be fine but if the community truely splits and the value is split (ie both coins worth approx $3k), I think that crypto overall will have lost out. It will put people off looking at crypto as it constantly forks etc and becomes ever more complex.
I know others hold different views but I don’t think any good will come of these constant hard forks.