Another interpretation of the double-slit posits a guiding 'Pilot Wave' separate from physical particles... aka DeBroglie-Bohm Theory or Bohmian Mechanics.

Apparently it's not popular among professional physicsts though John Bell investigated it a bit. Einstein had some unpublished notes in the 1920s about a "Gespensterfeld" (ghost field) that guided particles.

Born was influenced by this 'Ghost field' idea when he published his famous interpretation of the 'Wave Function' |Ψ|^2 as a probability rather than a physical field.

More info: Nonlocal and local ghost fields in quantum correlations. https://arxiv.org/abs/quant-ph/9502017

The way I've always thought of this is there are potentials for interactions and interactions.

Interactions act like point particles and potentials for interactions act like waves.

Arguing over the distinction is a bit like debating whether people are the things they do, or the thing that does things. There is some philosophical discussion to be had, but for the most part it doesn't really matter.

It does not. It shows that individual photons self interfere, so they cannot be idealized particles.

Are you getting confused with the photoelectric effect experiment?

Hmm? The double slit experiment definitely shows that particles are waves—weird quantum waves, but still waves.