Early on this seemed a pretty simple case of corporate misbehavior, but as with most issues that blow up on social media as cartoonishly simple battles between Good and Evil, additional details reduce that comfortable clarity. Since the service Bambu Studio connects to isn't required to run the software, their claim that keeping the service proprietary doesn't violate the AGPL might be valid after all. This would justify their objection to Jarczak publishing a fork that connects to the service without authorization.
I doubt that this will change the main discussion tho. No amount of information matters when people only glance at an issue long enough to swipe left or right and keep doomscrollin'.