This thread once again shows that most people were not playing the game as Nintendo had intended it.
The weapon durability system was part of the game's deeper combat strategy built on experimentation. The game encouraged you to use the different powers and the world's physics to combat enemies. Drop steel boxes on your enemies with Magnesis, lead them to a cliffside with food, then pummel them off with a two-handed weapon or draw them into high grass and set it on fire, etc.
On top of that you'd have to learn which weapons are most effective against which enemies (and the color ranking of enemies) so you don't waste valuable hits on a high level sword on a low level grunt.
Could the game have used a repair mechanic for weapons? Certainly, but if you kept running out of weapons it's because you were just hack & slashing your way through the game and not using the other tools that the game gave you to fight enemies.
Nintendo's folly was underestimating how lazy and uninspired gamers are and how many of them just wanted to hack away at enemies the whole game and only use the powers during puzzles.
But at least those gamers got another Hyrule Warriors out of that realization.