Classical Sunni explanations commonly describe angels as subtle luminous bodies, while some philosophers spoke of immaterial substances. The disagreement concerns their mode of being, not the revealed claim that angels are servants who obey God.
Neither classical phrase should be read as if it were a laboratory-verified account of modern physical matter. Subtle body and immaterial substance are historical metaphysical descriptions, meaningful within their respective philosophical frameworks.
What revelation establishes must be distinguished from speculative attempts to explain its underlying mechanism.