iPhone vs Samsung, Android vs iOS, BMW vs Mercedes ....
Nice question. Before everything else, I will make it clear that there's a small chance that bitcoin will be overtaken by any altcoins in the future. But if ever there is an altcoin that can compete with bitcoin, I think it would be
BITCOIN CASH. It's no surprise for me if, in the future, this offspring of bitcoin will compete its parent coin. Other than being an offspring of the best crpytocurrency in the world, people will probably choose this coin because of its relationship with bitcoin.
As of now, Bitcoin Cash is ranked no.2 as the most valuable cryptocurrency with a value of $1,252.91, next to Bitcoin with the value of $6,612.78. That's still pretty far if we are going to think about it, but who knows, anything can happen.