The classes need names for mechanical recognition and convenience, but they're not in-universe labels that are automatically applied.
Rogues can be scholars, police-investigators, spies, acrobats, musicians, blacksmiths, and so on. Their main focus is just being really skilled and having minimal magic.
Not all characters of the Paladin class would be called a Paladin either... some might get called "Champion" or "Blackguard" or some other term. Some might not have an official title... I sincerely doubt that my paladin of Sharess would be known by any title other than courtesan since Sharess's doesn't strike me worship as the type to have clear titles and hierarchies.
I kinda wish they'd change the names of "Monk" and "Barbarian" to something else because there is a constant battle to tell people "no, it doesn't have to be X narrow character concept". "Warrior" seems a culturally broader while still encompassing the mechanical concepts. But I haven't found a good term for "Monk" to avoid the narrow image that is associated there. Martial Artist doesn't really fit... pure martial training and art is more like what the Fighter is really. All the monks have hefty spiritual powers and their martial abilities are more side-effect than focus a lot of times... I thought about "Mystic" but that has other narrow connotations that aren't right. "Adept" is kinda vague and is very Shadowrun.
