I love that you wrote this. I’ve been thinking this for years and the easiest analogy I have for it is: Describe a radio wave, emanating from a single point, in 3 dimensions. The answer is: It’s a compression wave. I believe the particle theory is nothing more than a limitation of our ability to measure and that there is an electromagnetic “aether” which has a viscosity. After all, light is not instantaneous; it has a limited speed. So ... why? Hmm. The speed of a wave relates to the viscosity and elasticity of the medium through which it travels.