That's just it, what defines an RPG is it's ability to assume 'unique' job/class system because without it there is no such thing as 'roleplay'. Each jobs/classes are INTENDED to have a unique role so don't think of each job/class as being 'restricted' per say but think of it as each having "EXCLUSIVE capabilities" since a true RPG doesn't aspire to give the protagonist(s) every available ability at all times because otherwise it'd be no different than an either an action game or an adventure game ...
It is this unique roles or sometimes referred to as job/class systems in RPGs that separates it from EVERY other game genre out there ...
That is why series such as Dark Souls, Kingdom Hearts, and The Witcher or the likes of will NEVER be RPGs in a true sense ...
