well it just happen that my moto g1 battery died so I had to find a supplier (harder since it's not a shelf part anymore) and disassemble the phone (the battery is still glued, I'm waiting for the replacement to do that).
all your points are valid though, but still I like a bit of swappability.
10 years or so ago, a three-year old cell phone battery would still be good for maybe three or four hours per charge. Today, I’m using a 5-year old iPhone that still gets through a typical day on a single charge.
There are also battery cases, or external battery banks, whose introduction has solved most people’s battery-related questions, except “why are people still complaining about non-removable batteries?”