One thing that I see engendering some ill will is the inconsistency of Hobbes complaining that others think they own assets just because they modified them, while simultaneously claiming authorship and sole control over assets derived from others' work due to their modifications thereof. I don't think their overall stance is unreasonable, but some of the details at a minimum look a bit off, if not outright problematic. They don't want to get into licensing their works, but they also want to exercise full control, and they don't want to apply the same logic WRT their own derivative works that they are exacting upon works derived from their works. The origin of this doesn't appear to be Hobbes, but rather the unnamed modder [I'm suspicious I know who that is, and that guess does make me marginally more sympathetic to Hobbes] who they quote, but this highlights the underlying problem with reliance on norm-based rules: they only work until they don't, and they don't offer any clear redress once that moment arrives.
BLUF, if you want to exercise control over derivative works, you should be licensing your works rather than relying on good will and undefined, ephemeral community norms. It's not reasonable not to do so. If the community norms allow for you to post hoc impose a de facto implicit license, that worked out in this one instance, but I have a great deal of trouble sympathizing with Hobbes here since their whole rationale for not creating an explicit license for their works was that they felt it would be a hassle to deal with shared and derivative assets.