I do agree that newer jobs have a harder time being integrated to the world retroactively since they're, well, newer. It's strange when you think about how sage and pictomancer are Sharlayan disciplines of magic yet we never encountered a Sharlayan or Archon that practice either of those before, or that there's no, if not guilds, then active practitioners in the world outside of quest NPCs. This was not truly an issue with ninja and samurai, for example, as there's a bunch of those shown in Hinganshi and Doma. Many other expansion jobs have built in explanations as to why they aren't that common (reaper being seen as outdated by Garlemald, gunbreakers being more common in Bozja, the order of red mage being wiped out, etc.), but there's no real indication one way or another if sage or pictomancer are uncommon. I mean, clearly they are since we know very few individuals who practice them, but it's not made clear if we know few individuals because its rare, rather than the other way around. I digress.

Hopefully the job quests for pictomancer will take us to Old Sharlayan and establish them there.