One of the very first gaming terms I ever learned in an online game was bestowed upon me as a teenager in Ultima Online, and that term was tankmage. It was simultaneously a dirty word and a mark of pride: Tankmages, in those early days, were characters running around in full platemail and weapons but also had their magery maxed out, meaning they could kick the crap out of you more ways than one. You hated them and wanted the devs to fix the imbalance, but also you had to become one to survive and thrive.
Eventually, of course, EA did fix the problem in Ultima Online. Hundreds of times through the years, in fact, as successive teams of devs tried to find some balance among magic spells and armor and weaponry. EverQuest, with its class-based system, tried penalizing hybrid classes. Later MMORPGs have done away with penalties but kept the classes (or skillsets that act as classes). This can be done. Dozens of MMOs have found a way that works, more or less.
But the “if you can’t beat them, join them” mentality does still exist in many MMOs. Case in point: A recent thread on the MMORPG sub lamented the fact that Elder Scrolls Online kinda pushes everyone to be a mage in one way or another, even if they’re trying to be a pure warrior type.
Is this a problem in your MMO of choice? Are you sick of being a tankmage in MMOs? What MMOs are offering “pure” classes?