Also of relevance is the following:
Wave function collapse is switching from a theoretical superposition of isolated observables (outcomes), not yet formed, as a Definite Fixed State observable is produced upon observation; to a definite limited fixed state manifestation in space-time, emergent, reality. What exists in Object reality, prior to measurement, are proto- observables conjoined with the carrier.
The (Definite Fixed State) observables do not exist in space-time prior to the observation. Space-time is the output of sensory data processing that one fixed viewpoint formed from the sensory data received. The proto-observables conjoined with material-wave carrier exist in absolute Object reality space (no singular reference frame)for which there is uni-temporal (same time everywhere) passage of time.It is interaction with the apparatus and or measurement protocol that forms an observable from a proto-observable.
For the unseen spinning falling coin example the proto-heads observable can have many different orientations in absolute space that are within in the repertoire allowed by the flux. Absolute (source reality for all reference frames), Not definite as no reference frame and no measurement yet applied and not fixed as in flux but the output observable produced by the measurement protocol has only one orientation in space-time, heads up seen by the observer. The definite limited fixed state has been produced by the measurement protocol it is not representative of the absolute actualized (substantial) proto-observable- matter-flux carrier ensemble pre-measurement. The superposition of outcomes in a 2D mathematical space is an impoverished model compared to the variation of the proto-observable during the material-flux(or wave) carrier interaction.
The hidden variables that make the outcomes deterministic rather than merely probabilistic are substantial and unseen in absolute space. The foundational space that is the source reality for (definite, limited view) space-time emergent reality. The outcomes of the many experiments remain probabilistic despite the deterministic flux of the proto-observables because 'starting state' of a particle or other unseen object is never known. Thus representing variability of states, rather than uniformity within the population.