loverdrive
your favorite gm's favorite gm (She/Her)
You are building a fighter. You take a look at weapon table, crunch some numbers, come to the obvious conclusion: greatsword is the best weapon (I don't know how accurate it is to modern state of 5.5e, but if it isn't: replace greatsword with whatever other best weapon there is).I wasn't entirely sure what your goal was - you didn't mention realism but you also never mentioned fun either. "Realism" is the only possible argument I could see even a tiny bit in favor of this design, because yeah it is admittedly not 100% realistic that weapons and armor in DnD never break (assuming 5e Rules As Written). I definitely don't see anything fun in the idea, no matter how many angles I try to look at it from
You've built your fighter. Grabbed a greatsword and GWM feat. You are in an encounter. You have next no reason to ever do anything other than swing your sword, regardless of the enemy composition and whatnot. "I HIT HIM WITH MY SWORD!", over and over and over again.
Now, imagine your great sword has a limited use. Each high-damage swing is more valuable, and you better consider your options carefully: should you ignore mooks to not waste limited "ammo" on them and spend high damage on a tanky target? Should you switch to a sidearm to deal with them? Should you shove and grapple to get them out of the way? Should you try to form a gameplan around clearing out the mooks, each in one-two hits, wrench another big weapon from enemy's hands to "reload"? I don't know. Depends on the situation.
Does it make fighters weaker? Yeah, sure. Does it increase amount of thought playing a fighter requires? Also yes.