No. PoW is just an old name from the 199x spam fighting. The point here is planet-scale consensus, not "proof of work". One way to achieve distributed consensus in untrusted non-static environment is to randomly choose master for a given block. Imagine that everybody just throws a dice, and whoever gets 6 becomes that master. How we make sure that there is only one master for a given block, and that when you say 6 you really got 6 as i have no way of checking whether you even threw the dice at all? Satoshi's great insight was in building such a verifiable and statistically [for several minutes] single-master dice by using the good old hash based PoW.
Now, if somebody could come up with more energy efficient way to achieve that consensus at such a scale...