In fact, one of the great mysteries of physics right now is why only quantum objects have that property, and in order to figure that out we have to figure out what interaction “observation” actually is.
This does not stroke with my understanding of quantum physics. As far as we know there is no clear distinction between “quantum objects” vs “non-quantum objects”. The double slit experiment has been reproduced with molecules as large as 114 atoms, and there seems no reason to believe that would be the upper limit: livescience.com/19268-quantum-double-slit-experim…
This proves that the wave is in fact real, because we can see the effects of it.
The only part that’s proven is the interference pattern. So yes, we know it acts like a wave in that particular sense. But that’s not the same thing as saying it is a wave in the physical sense. A wave in the classic physical sense doesn’t collapse upon observation. I know it’s real in an abstract sense. I’m just questioning the physical nature of that reality.