People are just fighting over semantics at this point, trying to define what a 'generation' is when things are clearly evolving outside of that terminology. His comments can basically be boiled down to 'the PS4 Pro is a smaller iteration since it's basically the same architecture as before with a boost to GPU, while the Scorpio is a much bigger iteration since nearly everything about it's architecture has been changed (ie. 50% more ram, different GPU, no esram, presumably different CPU, etc)'.
This whole definition of 'generation' is a fool's argument. When Scorpio 2 is revealed 4 years from now and it's the same story (big boost but iterative in that it is forwards/backwards compatible) will we still be arguing about what a generation means? How far behind is Nintendo in all this if that is still the framework we are using?
It's not a fools' argument to consumers that are going to want to understand what it is they are buying and why. Even Sony botched this with the Pro, and Microsoft is not off to a great start either with marketing.
Is the Scorpio a PC like platform with spec bumps every few years? Fine, but a lot of console owners are more accustomed to more clearly defined upgrade cycles. When does the average consumer buy the new box and how long will Xbox game run on older models when Scorpio 2 rolls around? How long does "no one gets left behind" apply? It gives consoles a PC like paradigm that some might not be comfortable with. A lot of people like the simplicity. If E3 comes and Microsoft messes up marketing again then things might get messy. Marketing does matter. Confusion helped torpedo the Wii U.