> minimal incidents of battery fires or other mishaps
How many times have we had fires with Lenovo laptops, Canon/Nikon/Sony cameras, Dewalt/Ryobi/Makita power tools, and the million other devices that have replaceable Lithium batteries?
As long as users are using OEM batteries, there isn't any greater risk of battery fires, and as long as you price the OEM batteries reasonably, users will use them.
In fact I'd claim that it's safer to have a removeable battery, because if it starts bulging, you can eject it, and dispose of it safely, and replace it, instead of fussing around with first getting your precious files off the soldered SSD while it charges a dangerous bulging battery before you finally send the laptop in for $$$ service.
For Samsung it’s a much bigger impact. They have a wider temperature operating range and advertise heavily to police, construction and similar outdoor roles. The phones work but chew batteries — replaceable batteries would move more units.