I'll say it, and provide a source[0].

In that video, both phones are subjected to ever-increasing water depths until the S7 dies (very respectably) after five minutes at 35 feet, while the iPhone 7 continues to operate.

That suggests to me that both phones probably should have been rated IP68.

[0] https://www.youtube.com/watch?v=K05cTPeFfyM

I think it's a bit hard to make that claim with only one test with only one phone each (And it's a little convenient that the only guy who found the iPhone 7 to be more water resistant is the guy named 'EverythingApplePro').

That said, while you may be right they should be rated the same, that doesn't really help OPs point. Even if they should be rated the same, the S7 has a headphone jack and the iPhone 7 doesn't. If the headphone jack is really the problem then the iPhone 7 should be way better at handling water then the S7, and yet even in the video you linked the iPhone 7 was suffering damage from the same depths the S7 did. I would argue that even if the video is legitimate it's entirely possible he just got a "lucky" iPhone 7 that didn't end-up getting fried from the little water that got in, and the S7 wasn't quite as lucky. From one test you really just can't know.

Well, my iPhone fell into the water and it died too, just saying