A portfolio is a collection. You can have a new collection which has old things in it, as long the collection of things is different than any previous collection of things.

So just because it's a new "portfolio" doesn't mean each card in it is totally new. The no-AF card is clearly just refreshed, since it doesn't get a new name.

Anyway, just as at one point a few years ago someone documented that AA had 7 different definitions of "domestic" vs'"international" depending on what exactly was the operational aspect being discussed (baggage vs meals vs upgrades vs cabin names, etc, etc), it's quite possible for Amex to consider a card "new" for some purposes and yet "not new" for other purposes!

So there's no point trying to "prove" that Amex considers the card "new" in some wording, because that's doesn't prove they consider the card "new" for all purposes.