As you well know, there is no single experiment that proves that we are all made of nothing. I don't think that is your real question though. You are disagreeing with the conclusion. How about if I said that we are made up of waves of Space-time. Does that help you?
It's best not to bring Planck into this. IIRC he didn't believe in photons, and considered Einstein's usage of his quanta of action to be illegitimate or dubious at best. He had his own ideas about electromagnetic radiation.
Using that logic I shouldn't bring Einstein in either, he spent that last half of his life arguing against QED too.
People often make this comment about quantum electrodynamics. But there are dissenters, such as E.T Jaynes.
The equations have one degree less of freedom and that is huge.
Not really. I don't think it's correct to say that the solutions of, say, the Schoedinger equation, are waves of space-time. Weisskopf wrote a lengthy monograph on the properties of the quantum mechanical vaccuum. Why would that be necessary if it was nothing?