honestly i don't understand what you mean about bitcoin following eth? if you mean in terms of price of course what is happening now, the price of ethereum is more dominant following the movement of bitcoin prices in the market and in fact 99% it has been proven so far.
While Proof of Stake itself is an alternative to the Proof of Work system, Namely, a system in crypto asset investment where all algorithms in the blockchain system must reach an agreement before confirming crypto asset transactions that will be recorded on the blockchain, if you say so of course All altcoins can do this on the condition that miners must have assets of around 50% of the altcoins they mine, but in this case it will consume a large amount of electricity, as happened in China some time ago.