namseok middle children uwu! i think namjoon being the leader and their de facto english translator has a lot to do with it too. people tend to write him as authoritative because we see him taking on that role a lot! like, for example, i see the canonical age gap between namjoon and jk come up as a point of contention in namkook fics more than i see it come up in jinkook fics, even though the gap is larger with jinkook, and i don't think it's because of the actual age gap, it's more how people perceive the authority gap. jin has talked about intentionally not exercising his age authority in the group because he didn't want to complicate things for namjoon as the leader, and we see that come through in how he acts with the others too! which isn't to say that jin doesn't take his responsibility as the mat-hyung seriously or that namjoon isn't also a goofy mischievous little guy, just that there are certain dynamics we see at the forefront more often.