Title? I don't need no stinkin' title.
I think there are still people who aren't quite getting Point 1. For some of us, we don't really care what mechanical bonuses the druid can get. If they couldn't wear any armor at all, that wouldn't be the main problem. This quote most succinctly exemplifies the other position, so I'm going to directly provide an example situation to address it.
Here's a situation to consider--and it's what many of us are most concerned about. Someone creates a druid character. They have no intention of wearing metal armor. They are totally on board with the lore, etc. They most definitely are a druid.
In the course of playing the game, during their adventures, they end up in a situation where if they don't put on metal armor, someone dear to them is almost certainly going to die. Maybe the whole party needs to put on some plate guard uniforms to properly disguise themselves in a situation where the druid's magic and shapeshifting can't provide another option. They party (and players) put their heads together and try to come up with other solutions, and they are drawing a blank. Even the DM (who didn't expect them to end up in this predicament, but they took an unexpected path) can't see an easy way out of it. The player of the druid has a choice: their character puts on this armor, or everything is jeopardized, and the NPC(s) they are trying to rescue will likely die (the party is tough enough to fight their way out without a TPK--but no one has access to magic to raise the dead).
What we have here is an interesting moral (for the druid) dilemma. Do I break my vows and put on this metal armor to save those I care about, or do I maintain those ritual requirements and let them die?
What happens, in your (general "you"), game, if this druid player thinks it over, weighs the decisions, role-plays his druid PC agonizing over it, and then says: "I tentatively reach out and touch the armor with displeasure. I glance around with a somewhat ashamed look on my face, which then changes to determination. I put on the armor."
Do you, as DM, say: "No, your character won't do that"?
That's the main point a lot of us care about.
And the edge case scenario trope that always gets brought up on this topic that has never actually happened as far as I know goes to .... Sword of Spirit!!!! I'm surprised it only took us to post #77 to bring up this argument.
Listen, if this actually did happen, your DM is being an ****. There is no such thing as a scenario like this being forced on the player and DM. The DM controls the world, there is no reason to do this.