I don't think that is true, but I'm not gonna verify that as I don't have anything pre 3e at hand. I'll trust
@Snarf Zagyg will handle this.
That being said, inability to use spells and wildshape was my suggestion for consequence-based version of the armour limitation.
I've already been over this- this is a very peculiar "Max" reading that I've never seen that relies on some stray wording from Gygax and ignores the actual rules which are set forth in Eldritch Wizardry, the DMG, and the table at the front of the PHB, and are confirmed in all the extant contemporaneous materials.
In addition, it comes with its own problem (if you accepted it) - it would be contrary to what Max is saying now (which is that stray wordings without specific consequences can't be rules ... ahem). Because it doesn't ... have ... any ... actual ... rule about what happens.
Finally, by using "spoils" instead of any other words (such as "interferes"), it raises the uncomfortable inference that the wearing of metal at any time would forever destroy the ability of a druid to be a druid, which is the same (with added lore reason) as the rest of the 1e rules such as Magic Users cannot wear armor.
Milk that "spoils" is no longer good.
Spoliation of evidence is evidence that has been destroyed.
That's why Gygax uses the word in that way- "The reverse of the spell putrefies food and drink, even spoiling holy water. Unholy water is spoiled by purify water."
"The exorcise spell, once begun, cannot be interrupted, or else it is spoiled and useless."
So we can either accept the fact that the PHB and DMG lay out the armor rules (in a matter consistent with Eldritch Wizardry) consistency, or we can accept the weird parenthetical lore that Max is using that "metallic armor {destroys} the druid's magic powers."
6 of one ... half a dozen of the other. It's not really worth going into, since, again, OD&D and 1e players were very comfortable with these sorts of rules (Magic Users couldn't wear armor because REASONS, for example).