What in-universe reasons exist that explain why druid can use metal weapons but not wear metal armour?


In 5e, we are told that the druid shouldn’t wear metal armour:

Armor: Light armor, medium armor, shields (druids will not wear armor or use shields made of metal)

I believe this was true in older editions of D&D as well; "druids will not wear armor or use shields made of metal". Certainly the below quote seems to imply this…

In the 2016 sage advice, we are told that druids choose not to wear metal armour:

What happens if a druid wears metal armor? The druid explodes.

Well, not actually. Druids have a taboo against wearing metal armor and wielding a metal shield. The taboo has been part of the class’s story since the class first appeared in Eldritch Wizardry (1976) and the original Player’s Handbook (1978). The idea is that druids prefer to be protected by animal skins, wood, and other natural materials that aren’t the worked metal that is associated with civilization. Druids don’t lack the ability to wear metal armor. They choose not to wear it. This choice is part of their identity as a mystical order. Think of it in these terms: a vegetarian can eat meat, but the vegetarian chooses not to.

This question is not about what happens if druids wear metal armour, or whether certain druids might choose to wear it despite not being a common choice among druids.

My question is: why is there not a similar taboo around druids making use of metal weapons? Is there anything in any published material (ideally from 5e but I suspect that previous editions probably have more to say about this than 5e) that explains why druids are generally happy to metal weapons, despite the fact that they typically choose not to wear metal armour (or use metal shields)?


Just a reminder that this is not a designer-reasons question as I’m interested in lore-based answers, in-universe explanations, not any designer’s reasons from any edition as to why it was decided from a gameplay-based or mechanical point of view. I’m interested in the lore reasons only.


Related:

  • What would be the side effects on a Druid of wearing metal armor?
  • If I multiclass from ranger into Druid, can I still wear metal armor?