In part, allonormative society doen't talk about friendship because it's seen as a universal experience in a way that not even sexual and/or romantic relationships are.
This is true. There's also a long history of both different disciplines and the queer community having created different names for different type of attraction and relationships all through history.
Recently I was reading a book on Beethoven. There there's a quote of one of LVB's closest friends mentioning they had a "Romantic Friendship". And when I look up "Romantic Friendship" it basically describes what the aro and general aspec community now calls "queerplatonic relationships" (at least in some of its meanings). The author of the book also marks that a distinction between sexual relationships/love, sensual relationships/love and erotic relationships/love existed during those times.
Unrelated to that book, we also have disjunctive vs conjunctive, which is basically the split attraction model and varioriented vs perioriented.
Sometimes, I think that the aro community, especially alloplatonic aros, are so focused on these idea that they (and other aros) are enlighten individuals who know about types of attractions that "the allos" aren't aware of, when in reality they are just ignoring the existence of a lot of older terminology and the fact that humanity has being classifying love, relationships and attraction into different types since antiquity.