Customers want thinner and lighter, not heavier and thicker. People who need GPS all day are a 1% edge case.
Even if it were 10% or 20% of users wanting longer lasting batteries, Apple isn’t going to make 80-90% of users carry around a thicker, heavier phone 100% of the time, just to satisfy a small minority who sometimes need a lot of battery capacity. Even heavier users may only need the greater capacity a few times a month.
People can call it a thinness obsession/fetish or blame Mr. Ive if they wish, but Apple’s simply giving people what they’re asking for. Users who need more can serve their needs with a battery case or battery pack, without penalizing the vast majority who end the day at, who knows, maybe 20-60% battery—and are perfectly fine just charging at night.
Same with laptops. Most want thin and light, with decent battery. They don’t want thick and heavy, with 16 hours of battery capacity, when 8-10 hours is fine since they rarely use more than 3 or 4 anyway.
Again, it’s about give most users what they need most of the time, not about the heaviest requirements of the top 20 percentile.