Durability in Bloodborne was a terrible mechanic, because it was completely and utterly worthless, to the point where it was a complete waste of resources to even code up during development. It also exists as stat-pollution, and contributes towards overwhelming the player with numbers that mean absolutely nothing and drowns out the few stats that really do matter. If the main stat screen showed literally only your key 6 stats, HP, Stamina, and main-hand damage, new players would have had a tremendously easier time with the game. Instead they get drowned in stat spam.
It kind of sort of matters for like 1 or 2 weapons, but was a poor way to try to balance them.