vCenter itself wasn't really useful until version 4.x or so. It got a lot more modern at 5.5, the dawn of the recognizable vCenter, but up to that point people considered vCenter optional.

In much the same fashion, this PDM is just a bolt-on addition right now, nearly useless.
But its gonna become a locus for service management, and it will eventually be an integral piece of your cluster.

I would like to see PDM bring new DR replication capabilities to us. Sorely needed.