Agreed. Here’s my layman explanation: (based on Cassimir force) “Zero Point Energy” is the energy available to something in a ‘zero point hole’ in the universe. Imagine you are at the bottom of a well, and up at the top of the well is a 6000 gallon tank of water. If you had a pipe and a turbine generator, you could use the water in the tank to generate electricity until you drown and the well fills up. Whether you generate enough power to raise yourself out of the well determines how useful the project was. If you’re still stuck in the bottom when all the water drains out of the tank, then you were better off before you dug the hole.
Cassimir force is measured by excluding all electromagnetic and other forces from a space, then measuring the attraction of two plates to each other (a very tiny gap). Supposedly, this force is caused by the random quantum foam of particles popping in and out of existence all around everything, and by excluding them from the gap, you can use the universe as your tank of water.
ZPE people are trying to figure out how to turn that force into useful work.
In order to ‘theoretically’ model this and make it a reality, we need to understand several things:
The universe’s construction (the vacuum)
Matter’s construction (particles)
Energy’s construction (waves, transformation, etc)
So far, we don’t really know any of these to the definitive end-all be-all except that when it comes down to the Planck length, none of the things we do know, really seem to apply.