>>715890701 (OP)
I think one way to "fix" this is to look back at earlier editions of D&D.
Parties often had hirelings who handled the less glamorous aspects of dungeon crawling for them. Players would use them to test traps, barricade walls and doors, haul treasure in and out of dungeons, etc.
And looking to TTRPGs, CRPGs, ARPGs and fantasy adventure games in general, classes often give players a lot of non-combat utility. In WoW/XIV, professions and stuff like that are largely class-independent (at least afaik).
I'm of the opinion that the former approach is a lot more fun than the latter. I think it provides more opportunities to explore quest, class and level design than the latter approach.
So, I think one way to "fix" this is to add a fourth role—Specialist—and turn it into a quaternary, and I would seriously consider renaming the other roles to something like Offense, Defense and Support. I think adding a fourth variety of class that's less action-oriented but has flavorful out of combat utility could go a long way in revitalizing this style of game design.
I think that making the gameplay experiences among various classes symmetrical or even balanced is a lot less important than giving them compelling reasons to share the same spaces and interact with each other, as obvious as that might sound. The fourth role could essentially just be added on top of the pre-existing trinity and still manage to add a lot to it while playing an entirely asymmetrical role in PvE content, I think.
The Specialist role could include classes like the Thief, Tinker or Archaeologist. It could even ironically house classes like a Freelancer or a Tourist.
Even more important than the quaternary I'm proposing would be the perspective from which I believe MMO classes should be designed: they shouldn't be designed primarily for the sake of balancing combat but for the sake of providing a wide variety of experiences to have and roles to fill to the player.
