I think it will save to say PS5 and Xbox Scarlet will be around 499 USD due to inflation alone. And all price already expensive, and even mainstream GPU price is now above 399 USD (back then it was around 250 to 300 USD). So if PS5 and Scarlet targeted at 399, PS5 and Xbox could ended underpowered and less jump in performance compared to 7th gen transition to 8th gen, PS5 and Xbox need to at least targeted price around 499 USD.
The jump in performance was always going to be smaller. Three and a half node shrinks versus two shrinks. That's simple physics, right there. Although one could reasonably argue the PS4 and the XB1 erred on the conservative side as far as their APUs were concerned, perhaps overcorrecting from what had happened in the seventh generation. So the leap could be larger at the expense of power consumption.
Another thing to keep in mind: the leap in cost, per mm2, from 28 or 14 nm to the 7 nm node. The cost of a ~300 mm2 chip in 7 nm is significantly higher than the cost of a 28 nm chip of the same size. Potentially enough that the route of higher clocks and a more expensive cooling solution would be preferred instead of trying to fit more CUs in there.