I used to not be sure about the whole bitcoin cash/ bitcoin debate but after watching Roger Ver interviews I'm starting to be convinced that big blocks are the way to go.
Try not to confuse yourself there is just a single bitcoin with "BTC" ticker, top 1 on coinmarketcap, That's it. Are you referring to those new projects possibly a fork claiming to be superior to bitcoin? bitcoincash would never replace bitcoin those are two different cryptocurrency.