>>11735300The only thing to me is that there is kind of an archetypical idol, so I can kind of say "Well, X and Y don't naturally fit that as well, so maybe they're Niji-ish?" for some Holos, while there's not really an archetypical liver so even with the more idol-esque ones it's like "yeah, but they can do (and probably ARE doing) that in Nijisanji just fine."
But even in the first case like, they chose to try and fit that idol mold, and in theory any of the Niji girls could too (although I can't even imagine what it'd look like for a lot of them), so eh?