from 0 to 2000$ in 6 month. bitcoin can't do that. people will realize bitcoin cash is better. but now people buy bitcoin because they think bitcoin is gold. not a currency type
First of all you need to understand that such a value growth has taken place from zero to $2000, because it is the element that got forked from bitcoin's main chain. If it is something else it could have never reached this level, so even in its growth bitcoin's contribution is there. Upon this bitcoin cash won't go above bitcoin at any point.