Seriously smartphone manufacturers, stop trying to shave 3 yoctometers off the thickness every 6 months and give me a phone that is thicker but has a battery that lasts a reasonable amount of time and cycles less deeply so it has a longer life.
4 - 1420 mAh
4s - 1432 mAh
5 - 1440 mAh
5s - 1570 mAh
6 - 1810 mAh
6s - 1715 mAh
7 - 1960 mAh
It dipped a bit from 6 to 6s but other than that they have been consistently increasing battery capacity.
(Btw, plus models have more; the iPhone 7+ for example has 2900 mAh. On the other hand, they drain more for the screen.)
SE - 1624 mAh
Battery capacity increases alone are meaningless when the hardware connected to it drains it just the same.
What were these thicker heavier longer life phones of which you speak? I don't recall there being any of those to have rejected.
Maybe you mean ye olde feature phones or their predecessors. I don't think that's a fair comparison.