I don’t really buy the Alice-Alex dichotomy. “Allie kinda has a good point here” often coexists with “Allie’s thinking about this is pretty distorted and not an accurate description of reality”. Often Allie has blind spots or tunnel vision around this topic, or their understanding of the principle at stake is idiosyncratic and not a good guide for others to be consistently following, or their application of the principle is pretty selective relative to its explicit meaning (e.g. they mainly apply it against people who they already oppose for other reasons), or there’s something funny about how they came to have this hobbyhorse. Maybe an Alice-Alex spectrum is a good enough model? Or maybe it’s better to split it into two dimensions, the extent to which they’ve locked onto something true and important and the extent to which their own thinking about it is screwy.
I’m also unsure about the emphasis on “principled”. Sometimes it seems more like: there are certain patterns of things that deeply annoy/frustrate/offend someone. When one of those things happens around them, they point at it and complain. But the sorts of things that trigger someone’s complaints are a different category than the things a person says about the things they complain about. If a person complains about a thing by saying that it violates such-and-such principle and presents themself as a champion of that principle, that doesn’t necessarily mean that this person in fact is unusually rule-based in abiding by that principle and trying to apply it consistently with high standards. (Though there is typically some relationship between their complaints and that principle.) “Annoyingly loud about principle X” is not equal to “loudly & annoyingly principled about X”.
Sometimes the main potential contribution of an Alice-like person is directing attention to things that don’t fit smoothly in the conversation, and which otherwise might not be talked about much or even (by many people) thought about much. In those cases, what Alice has to say about those things doesn’t add much value. It may seem like Alice has some special insights, but those are just low-hanging fruit that you could get just by paying attention and doing some thinking about the topic. And Alice’s version of those insights might come with some distortions, attitudes, animosity, etc. that aren’t necessary or fitting, such that if you’re relying on Alice then you need to do a lot of work sorting out the actual patterns in reality that she’s been tracking from all the other stuff. Once Alice has directed your attention there, the main thing to do is to look at that part of the world and think about it and use your standard epistemic processes for making sense of the world. (As in my first paragraph, there are two dimensions here where different Allies can have more or less hard-to-independently attain insights, and different allies can also have more or less distortions & nonsense.)
This is part of the trickiness of writing the post without examples, which would better pin down where in Alice-Alex-space we’re looking. But, as you got into in another comment thread, there’s other trickiness in writing the post with examples.