To answer the OP question: Depends on the adventuring day and that holds true in all editions, from 1st to 5.5. If the time between rests drags for long enough, a fighter will outdamage a mage no matter what. This is a core concept of D&D and other systems as well and there is no need to change it because it is an excellent tool for the DM to keep things enjoyable for everyone. Let all characters have their moments of glory, it adds to the fun!