Aside from the relative difficulty in finding both tin and copper as Termite alluded to, bronze is also heavier than iron and more prone to bending. This isn't necessarily a bad thing; because bronze is heavier it's suitable for weapons like warhammers and axes because it'd give them more heft and cutting/smashing power, and a dull axe will still fuck you up. It does make bronze almost objectively inferior for armor, though, and bronze swords don't hold their edges well and are more prone to bending than iron or steel ones.

Make no mistake, at this point (and until metallurgy becomes a lot more advanced and widespread, perhaps at a 1200-1300s tech era) steel production would be so limited in scale and time consumption that only the wealthy would be able to have access to it.