The main advantage of a removable battery is that it is easier to replace when it is worn out.
A critical advantage, for sure.
But don't overlook being able to easily swap the battery for a much larger one with a TPU (or better) case. I will never own a phone with a battery under 10,000mAh again, because I quite prefer having a big, heavy phone. I know it's on my person. To me, that's important.
I'm a tiny market, but that's the point of user-replaceable shit.