I think a tree falling is a little different from the double slit experiment, because the outcome of a tree falling will always be the same. That question is a little more philosophical about whether the pressurized air waves a falling tree makes are actually “sound” or whether it’s the interpretation of those waves done by our ears and brains that actually counts as “a sound”

The double slit experiment actually has two different outcomes, and that’s just some of that freaky quantum voodoo shit.