It doesn't looke like a reasonable assumption to me.
It looks like believing in fake rumors, then rationalizing why the fake rumors don't turn out true.
Unless you have any reliable well to determine which rumors are true and which are false, you're only doing the same thing and rationalizing after the fact.
We know that plans change and products are delayed (or outright canceled) all the time. It's hardly an unreasonably assumption.
Navi was never intended to arrive at CES.
The first part you have no way of knowing, so you're just rationalizing after the fact. If you look further back at
information AMD themselves verified, they were clearly looking to have Navi available sooner if possible.
Vega 7 was not a "panic response". It was always intended to be both a Pro card and a consumer gaming card.
The only reason that AMD can even sell Radeon VII is because NVidia jacked up their own prices with Turing.
It's one card at the far end of the "consumer" market. There's no product stack, it is just Radeon VII and the rumors are that there might not even be more than 20,000 of them sold.
It's basically another Frontier Edition card at best. It's not even good as a stopgap. It only makes sense to show it off at all if you don't have anything else, because it's just that bad.