Have you thought about why since the creation of ethereum and as a number one leading altcoin it has not done so greatly proportionate to the number of years it has existed. Simple, it due to its POS nature, and a switch by bitcoin from POW to POS (which I don't see it happening) would mean that bitcoin will lose its independent status and value to which other cryptocurrencies  follow suit at every moves it makes and become like every other cryptocurrencies. I understand your fears and it's mutual for some of us that care much about the future of bitcoin. However, I am optimistic that bitcoin won't lose it thrust to becoming POS, it's just not possible.