Nomads...

[Treewyrm]

player wise, few are impressed by the nomads anymore I'm afraid. Everyone seems to know of their existence, except a very small minority

Player-wise, as you noted, absolute majority played SP, hence they know what happened, again, player-wise, except that not everyone here is Trent Edison or any of his companions. Amount of what your character know, not you personally as a player, would depend on other factors, such but limited to like relevance the character had to the events of SP campaign. Naturally average joe sixpack would have a very limited knowledge, like knowing there are things out there, overheard something at some point, but where they are coming from or what they are really, some of those questions not even the Order can answer without falling into hypothesis and theories. "Impression"... like saying "I'm not impressed by SP campaign", to each own I'd reply then and keep walking as I were. Inaccurate wording I suppose, hence missed the point of what you actually was trying to say.