There are different *interpretations*, but all interpretations agree on the predicted results of experiments, which is why they are *interpretations*. The actual predictions are supported by all the investigations into atomic, subatomic, and even chemical phenomena over the past 100 years or so. That is very, very far away from being 'purely theoretical'. Our modern understanding of solids, of chemical bonding, of spectra, of lasers, of semiconductors, of nuclear events, of the structure of atoms, etc are ALL based on quantum mechanics. Those have very real, practical effects.
The one 'interpretation' of QM that is deterministic is Bohmian mechanics. The problem with it is that it is non-local and can't be extended to deal with the field theories, including QED. In particular, it doesn't do well with dealing with anti-matter. it is purely a version of the classical Schrodinger equation and not of the Dirac or any other relativistic equation. In fact, it very specifically violates special relativity.