How quickly we forget history. I'm not going to say they were the absolute first to do this as I'm not doing a full survey of 2007 phones, but before that (a) there was not a single phone I or my friends had that didn't have a simply replaceable battery and (b) there was a ton of conversation and press when the iPhone was first released about how unique the decision was to have a glued-in battery here.
For contrast, here are instructions for replacing the battery on the famous Nokia 3310 https://devices.vodafone.com.au/nokia/3310-2017-proprietary-....
Let's be real here: if having difficult-to-replace batteries was a money loser for Apple and other manufacturers, they would fix the situation in a heartbeat - it's not like this is a hard problem. The only reason they do this is because of desired planned obsolescence - tons of people will think "Oh, getting the battery changed is such a hassle, might as well get a new phone."
Again, essentially every consumer electronic device pre-2007 (except maybe some Mac laptops?) had easily-replaceable batteries. Convincing people that using glued-in batteries was a necessary design change, instead of a corporate decision to make more money, was a real coup for corporate marketing.
Compared to a modern iPhone you can throw in a pool and dig out safely a few minutes later.
Batteries post 2007 have gotten REALLY good, the capacity/weight ratio has gone up so much that swapping batteries mid-day isn't a thing people do. Drones weren't a big thing in those times because you couldn't get enough power to lift one up. Now a 249 gram DJI drone can fly ~45 minutes on a single battery that's about the size of 2-3 matchboxes.
I still remember the laptop I had around that time that had two batteries so that I could swap one and still keep it running with the other.
On the other hand my current M2 MacBook lasts for two full workdays without charging easily, even more if I just sit in meetings and don't do anything CPU/GPU intensive.