http://www.polygon.com/2017/3/2/14792066/nintendo-switch-friend-code-response

Seems that friend codes are temporary and will become optional in the future (probably when the paid online launches).

Here's the full statement from Nintendo -

"Several methods can be used to add friends as quickly and easily as possible: · By linking Nintendo Switch to your Nintendo Account, your friends from Miitomo and Super Mario Run will appear as friend candidates so you can easily send them a friend request. Also, we are planning it so that friends from social networking services will be listed as candidates, too.

In the future, you will be able to send a friend request to friends associated with your NNID (Wii U/Miiverse) and Nintendo 3DS.

In some games you will be able to use an in-game interface to send friend requests.

You can send friend requests to those who have played with you recently.

You can establish a friend through local wireless communication.

You can also send a friend request by using a friend code."

It is still missing the entire point.

There is literally no reason to surface, in any form, a damn 12 character code. That is simply a barrier to usage, regardless of how much other crap you put around the code.

All that is needed is to only display/search/use the Nintendo Acccount. That's it.

So looks like they aren't phasing out the NNIDs :p

Codes are a bit annoying, would prefer if you could just search their names :/