The variation of the double split experiment that supposedly proves that observance "changes" the outcome, is only a thought experiment, and therefore can be flawed due to incorrect thinking. Obviously, the basic double slit experiment which shows the wave/particle duality of light is done in practice and therefore empirical.

I like most on here have followed your thinking at some point, but have had to ditch our intuition along with comman sense and a good part of our sanity when we found out we were lost down the rabbit hole after schrodinger's cat ate our breadcrumbs.

An observer changing the outcome is a very real repeatable experiment with non wavey results.

https://physicsworld.com/a/do-atoms-going-through-a-double-s...

It's similar to the problem that has been highlighted here by OP, to quote the artical I posted

"Indeed, the results of both Truscott and Aspect’s experiments shows that a particle’s wave or particle nature is most likely undefined until a measurement is made. The other less likely option would be that of backward causation – that the particle somehow has information from the future – but this involves sending a message faster than light, which is forbidden by the rules of relativity. "

And how wave/particle duality is possible without superposition?