[markovs_gun]

I hate this phrase because how do you even define "made of nothing" or "gaps between" when talking about objects as fuzzy as electrons, and how would you define where something "is" or "isn't " other than interactions? If an electron cloud is interacting with another electron cloud why do we say that space is empty? Because the measured radius of an electron is so much smaller than we observe?

[monadINtop]

Like you say, it's just a more intuitive classical analogy for people who don't want to waste good years of their life (like me) to understand the mathematical detail of theoretical physics.

The electron doesn't actually have a measured radius (in our current theories). QFT describes it as point-like excitation of an underlying quantum field. The only connection between our quantum theories (that is really just slightly hand wavy math) and reality is that our theories can predict the statistics of observing a particle or interaction in a given state. So maybe a slightly more coherent explanation is that for a given region between atoms in solid matter, the probability of observing an electron (or any particle) is extremely small. Its like a quantum mechanical cat who's territory extends across mountains and forests, you're probably not gonna stumble across it on any given day, unlike a (quantum) house cat that lives in someones apartment. More generally there are no big "lumps" in the wave-functions, it's very thinly spread like too little butter on toast.