that was my reference point too. iOS 10 on 7+ which was peak battery, then X on 11 was a nosedive. XR is like the old days and then some.
I'll be pretty happy with Pro and Pro Max having that level if it is true, if for no other reason than because once they have all three phones of varying sizes with amazing and appreciable battery life, everyone will then be adjusted and there will be no turning back without (non paid) critics scolding them for it. The disparity in battery life has been a tough thing, cause it depends what device you're coming from.
Heck even SE on iOS 12 is not great battery, iOS 10 it still is decent 3 years later. I can only imagine iOS 13 on A9 devices is a showstopper battery life wise across the board (SE/6s/6s+) and getting there with 7 series since my 7+ kinda sucked on iOS 11.
Agreed on the Xʀ being amazing, and about what you said about the 7+: a friend’s 7 on iOS 10 had the same battery life as my 6s on iOS 9. That same device on iOS 11 was getting 60% when compared to the exact same 6s on iOS 9. iOS 12 made it drop even further, I think it was 45-50% of my 6s on iOS 9.
I tested an iPod Touch 5G on iOS 6.0 in 2012: 6 hours and a half of 20% brightness web browsing.
I tested the same iPod Touch on iOS 6.0 in 2015: 6 hours and a half of 20% brightness web browsing.
I tested the same iPod Touch on iOS 6.0 in 2019: 6 hours and a half of 20% brightness web browsing.
Three tests, nearly 7 years apart, same iOS version = same result.
I couldn’t believe it. That’s why my 6s on iOS 9 was getting the exact same battery life with 87% health and three years later.
As you say, I’m also assuming that iOS 13 will absolutely demolish the SE and the 6s’s battery life. The plus might escape due to sheer battery size, that’s why iPads maintain good battery life when updated, even if they drop a little, it doesn’t really affect people too much.