I wouldn't characterize myself as "the GOS camp" (I use LineageOS) I just happen to agree with them sometimes, and this is one of those times.
I do imagine this response is to some degree influenced by their beef with /e/ (an OS I don't have a high opinion of either, but for other reasons). It just seems to me that people see "not google" and think it's a good thing, but a gatekeeper determining which OS you are allowed to use with what apps is fundamentally a bad idea even if it's not google.
Ironically though this makes the reverse a bit more defensible (i.e. using an LLM to reverse engineer a proprietary app) because that proprietary app's source code is less likely to be among the publicly available dataset.
But I imagine the corpos aren't going to look fondly on that for obvious reasons.