alt Hacker NewsSoap bubble bokeh comes from overcorrected SA. Onion rings and related brightness anomalies/unevenness in bokeh are mostly the result of molded aspheric lenses. Stopping slightly down has not significantly impacted bokeh (apart from apodized lenses) since rounded aperture blades have been invented about fifty years ago.
The iPhone 18 aperture does not have rounded blades (except the tip). Six hooked blades, very truncated hexagon aperture (perhaps exactly a regular dodecagon, it’s a little difficult to tell from the promo images)