Hello everyone!
Is it possible simply to accept the most usual QM boldly and straightforwardly like this,
All the Nature's observable physical properties are the outcome of the universe wavefunction collapse;
we cannot - even in principle - know (scientifically) how exactly that universal collapse comes - but it seems coming according to the Born Rule so as to maintain the apparent Nature's statistical "naturalness";
- that's why the usual QM is FAPP-applicable, every prepared laboratory wavefunction being a "branch" of that universal collapsing wavefunction.
(So every textbook quantum system is a "toy universe", its properties being formed by the abstract collapse.)