I'm guessing those numbers are split by the timeframe associated with the generation making the PS4 gen $9B figure not for truly the PS4 hardware up to now, but the figure of profits for 2013-2020.
And with the PS4 proving to still be extremely strong a significant part of PS5 gen $10B profits must be related to PS4 hardware.
Edit: the document confirms it:
Its by years and most profitable years of "PS5" gen profits were in the first 2 years (Covid years) where most of the profits would have come from the PS4 hardware as PS5 was sold at a loss. Now that the support is down for PS4 the profits are also way down for 2022-2023 and this is despite it still having a strong leg.
Those number looks good at first but with analysis, they do display the current concerning trends in the industry that are leading Sony themselves to review its operation and bolster PC support.
