Specification (takhṣīṣ) is an important function, but it does not follow that every «huwa» before a predicate must impose an identical, context-free type of exclusive restriction. Other functions include reinforcing predication and differentiating a predicate from a modifier.
إِنَّ اللَّهَ هُوَ الرَّزَّاقُ
Indeed, Allah is the Provider.
The wording combines emphasis, attribution, and exclusivity. A sound interpretation looks at the whole expression and the hearer’s situation, rather than extracting the full meaning from one particle.