Chaosmancer
Legend
Someone in some rare situation possibly doing a thing is completely different than practically everyone always doing a thing. This is not difficult. Metal armour is simply better than non-metal one and in absence of restriction or an incentive to wear other types of armour it becomes a de facto default.
And if it was so important to have other armor materials, they would have included rules for it. And if this was about mechanics, then the Sage Advice wouldn't have directly stated that this was never a balance issue.
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I also notice that you ignored my question at the end. Do you think druids would hate the undead, because they are unnatural.
See, most people would say that yes, Druids would hate the undead, because they are unnatural beings that defy the cycle of life and death in the world. And yet, we have the spore druid. A druid that creates undead.
A theme of druids, subverted by a more specific druid. Because, while themes are important, there are many different ways to interpret themes. And players should be free to make their own decisions on what their characters believe.