well i think a lot stayed with samsung or android after the note 7 nightmare was due to the high amount of offers/deals samsung offered customers in terms of carriers to make people stay.
i suppose android and samsung is different when it comes to battery life and stability. as the Pixel most likely you will find is very smooth and give you great updates like with IOS
that said even last year i was not happy with performance and battery life on my S7 edge so lets not act like things are great in that area. this year? hopefully that has changed. S8 plus for example seems to have better battery life than last years models already
IPhone 7 doesn't have good battery life either. Don't talk about standby time but in usage it is no better.
Updates? Quite ridiculous on iOS. If you don't move to the latest version, you can't update or install new apps from App Store. My iPhone 4 is pretty useless but my s2 is running along fine.