Regarding disbelief that the consoles are going to launch at such high spec points:
Note that current 7nm products are paying through the nose for silicon, and total 7nm capacity has been relatively low, and shared between AMD and all the high-end phone manufacturers (esp. Apple). TSMC advertised 7nm capacity just doubled, and Apple is moving off the node to 5nm for it's next flagship. Also, N7+ gets about 15% density improvement over N7.
What I'm getting at here is that the expectation of console costs should not be based on comparing costs with current products. What would be cost-effective to put in a console that launches today, and what will be cost-effective to put in a console when they actually launch, are probably going to be very different things.
I very much agree with the sentiment that it would not be smart to purchase a GPU today with the intent to use it for future cross-platform titles. By the time the consoles actually launch, the hardware in them is probably not going to be equivalent to high-end, or even "upper middle class" GPUs, that are on the market at the time. Which will be very different beasts from what are on the market at the relevant price points right now.