AFAIU perspective compression is a key element of the illusion - when the moon gets closer to the horizon/treeline/skyline, our mind creates a sort of vignette

AFAIU perspective compression is a key element of the illusion - when the moon gets closer to the horizon/treeline/skyline, our mind creates a sort of vignette with limited FOV for perceiving it, in which the relative size of the moon appears larger (because our focus has become inadvertently and subconsciously narrower).