Eloren Wilds

The additional mana is produced by Eloren Wilds, not the permanent that was tapped for mana.

If an ability of a plane refers to "you," it's referring to whoever the plane's controller is at the time, not to the player that started the game with that plane card in their deck. Many abilities of plane cards affect all players, while many others affect only the planar controller, so read each ability carefully.

You're "tapping a permanent for mana" only if you're activating an activated ability of that permanent that includes the {T} symbol in its cost and produces mana as part of its effect.

A face-up plane card that's turned face down becomes a new object with no relation to its previous existence. In particular, it loses all counters it may have had.

The chaos ability prevents the affected player from casting permanent spells (artifacts, creatures, enchantments, and planeswalkers), not just instant and sorcery spells. It doesn't stop the player from playing lands or activating abilities (such as cycling or unearth).

Eloren Wilds's first ability affects any permanent players tap for mana, not just lands they tap for mana.