Posting this insightful comment from chat so it doesn't get lost:
The Stack's basic "Back it up!" principle should, in theory, be sufficient for lit.se as well.
Unfortunately, in my experience a significant number of Stack users are members of that part of the wider population which has not been trained in the difference between assertion and support.
This means most attempts to ask that support be added to an answer are interpreted as a challenge to the user's expertise, and that creates a defensive attitude which opposes the support-based culture underlying the best Stack content.
I've seen it on multiple Stacks, where opinion-based subjects are considered either free-for-all open game for unsupported speculation, or are considered impossible to answer within the Stack structure.
Literature can't succumb to that false dichotomy or it will crash and burn where some other Stacks can still survive with limited function.
But we don't actually need to invent extra policies for answering questions here, at least not yet. The simple notion that claims need explicit support--ANY kind of support--should be enough to get us off the ground, with multiple answers providing multiple critical lenses.
This attitude (that claims need support, but not specifying the kind of support) creates a space for responses ranging from reader response (experience-based support is a major part of several Stacks already! see rpg.se, parenting.se, gardening.se, etc) to authorial intent.
