So it's a temporary situation to do it this way until they can get enough stock and work their supply chain to provide additional batteries? What a non-story.
I don't see anything to suggest that this policy will change in the future, they probably don't want to risk someone burning their house down while trying to remove a glued in pouch battery and then blaming Apple for it.
Incidentally on the flip side of this, I got a free new battery out of the keyboard replacement program because they replace this whole top case assembly for keyboard replacements as well.
I hoped that whole keyboard warranty extension fiasco would encourage Apple to stop gluing everything together so much and design for individual components to be replaced again, but I guess not.
Whoops, so they do. That's a repair I wouldn't want to touch by myself but good luck to anybody who does!
The last Mac laptop I did repairs on was a snapped hinge and man that a painful process. Similar boat with having to take the entire computer apart (including the screen assembly). These days I'd be much happier to pay someone to deal with that, but doing it yourself is certainly the affordable solution and I'm glad that self repair continues to be an option.
I replaced the glued-down baggie-cell batteries in the laptop I'm currently using. It was a giant PITA, and I was very wary of burning my house down the entire time. It would absolutely be worth the cost difference to secure and protect the batteries in any other way.