It is possible that it will even out, but there are very plausible scenarios with no stable equilibrium for BTC. It all depends on how the market reacts to the changing behaviour of the network.

It's more related to mining difficulty than market cap. Bitcoin Cash has a mechanism to adjust difficulty with declining hashpower which BTC does not. They both respond differently to declining hashpower as a result (Bitcoin is arguably designed to die in a catastrophic hashpower collapse).