The listener’s epistemic state influences rhetorical choice. One listener is uninformed, another undecided, another convinced of the opposite, and yet another knows a truth but overlooks its implications. Qasr need not have identical force in every setting.
«مَا مُحَمَّدٌ إِلَّا رَسُولٌ»
Muhammad ﷺ is only a messenger.
In its setting, the verse focuses on messengership and the fact that messengers are human and subject to worldly events. It does not deny the Prophet’s other established virtues or attributes. The exclusion addresses a particular misconception of the audience, not every conceivable quality.