they should go the 911 way...keep the name, change the headlights design every year

According to the DOJ's antitrust complaint, the improvements are negligible because of lack of competition in premium smartphones insulating Apple and allowing them to deliberately target "good enough" and eschew new and especially expensive features. If that's true then this crawling-progress is entirely artificial and biennial announcements wouldn't really make a difference.

https://storage.courtlistener.com/recap/gov.uscourts.njd.544... (point #14)

The cadence is not just about shipping marketable products and features.

It's also about iterating on internal capabilities, processes, technologies across design, sourcing, manufacturing, etc.

What makes it into each year's phones is what's had the kinks ironed out, and all the commercials sorted.

I wonder why we don't get biennial [S] release years at all anymore. At this point, more of the iPhone's lifetime has been without S releases than with, but they could probably sliped back into that cadence and no one would've complained.

16 -> 16s -> (17 + 16s /w discount) -> 17s -> (18 + 17s /w discount) -> ...

I'd even say that the Pro could be it's own line. The unibody aluminium and tweaked looked would've been a good starting point for "iPhone Pro". (then iPhone Pro 2, 3, 4...) That could free them from having to segment the market for every single iPhone release by "pro" features, since the new pro in theory might only ever need a biennial release.