That being said... the Xperia compact series is all the proof you need that a small phone can have it all. Good battery life, flagship camera (though understandably you won't have as many sensors as a giant phone), a headphone jack, a microSD card, good battery life, waterproofing, a fingerprint sensor...
It's such a shame that people continually insist that technology we HAD in 2012-2016 is impossible today. All I want is an Xperia Z3 Compact with modern bands and software support.