In my experience bitcoin cash is a fork of bitcoin even BCH is faster and cheaper to use due to larger blocks but still it'a seen that most of the people are using BTC than BCH so why is bitcoin doing better than bitcoin cash?
I think it is because peoples already trust bitcoin value in the market is real. Cryptocurrency is not only about faster or cheaper.
There are many altcoins that have a better speed and fee than bitcoin, but why the value still far from bitcoin ? it is because most peoples believe btc.