We hear it time and time again and last weeks poll confirms it people prefer stock Android. Overwhelmingly so, this option got a cool 42% of the vote while the second place Samsung was way behind with 15%.
Android gained extensive customization features a while ago it started with custom launchers, lockscreens and keyboards and ended with native theme support. These days you can tweak stock, non-rooted Android quite a bit… unless a manufacturers skin gets in the way.
We have a tie for 3rd place Motorola and Xiaomi at 10% (were even willing to include Sony at 9%, its close enough).
By the way, in the comments you heaped the praise on Nova Launcher indeed, its a highly capable, very customizable launcher. Unfortunately, there are limits to what even Nova can do (e.g. Xiaomi/MIUI can be overly aggressive in killing background apps).