What? It's the opposite of literally all these things.
I feel like GGP is the one with the preconception about the name "power plant," while the industry (as shown here) is starting to use it to be this broader term encompassing distributed generation and price-influenced demand, etc etc.
When people thinking about generation they think about something different than reducing demand, but it's critical to start seeing that those can be the same thing, in certain circumstances.
So I agree that the VPP terminology leaves a lot to be desired. I prefer the more generic "DER" terminology, because it is more descriptive; either a generator or a load is an "energy resource", and "distributed" is a good description of what is unique about these particular energy resources.