But I don't believe reality is like that. The alternative to the wave model is the particle model. But that model fails in many places. Yet there appears to be some superposition, such as in a Bose-Eintein condensate where there are indications that thousands of particles start sharing a volume of space. Or photons which seem to be able to pile up in the same location.
Superposition is a property that waves have in general.
This includes wave-functions of quantum mechanics. This means that two electrons around the same nucleus cannot have the same shape of wavefunction. Personnally I don't believe in wavefunctions. They are a convenient and effective way to make predictions and calculations. But I don't believe reality is like that.