Hello. I think you are mistaken with the positive assessment of PWM. You provided a graph for a length of 50 milliseconds, that is why it looks smooth in scale. If you make a graph in a scale of 2 milliseconds as in all your tests, the amplitude will not look so smooth.
One correction to the article: you cannot dive to 6m depth or actually even 1cm depth with an iPhone. Apple expressly states that warranty is void if any moisture or water is detected inside the phone and that getting the phone wet (even in rain) voids both the warranty and any bought AppleCare. Learnt this the hard way when my FaceID stopped working when answering a call in pouring rain with my IP13 Pro.
The IP rating is therefore useless at best and badly misleading at worst when it comes to iPhones, buyer beware!
Such an odd one; it's the latest flagship, it tops charts in some numbers, but benchmarks show how the 15 Pro and (more surprisingly) the non-pro 16 fare better for no good reason.
Oh and enjoy your expensive AI phone with no working AI features yet.
If you want the best iPhone, then you'll have to reach for the Pro series, as only here will you get a 120 Hz display, the fastest SoC and the best cameras. Exactly this is offered by the iPhone 16 Pro and much more, as by Apple's standards, lots has been changed on the new Pro model. It even features the same camera setup as the iPhone 16 Pro Max.