It will sell anywhere between 20-80 million depending on market conditions. But this isn't what decides Sony's fate as a platform holder. What makes a digital-only future particularly dangerous for Sony is that they may start losing their existing players, as even the PS5 is turning digital-only. Basically: we're getting a digital-only future TWO generations earlier than expected (or a gen and a half if you will).
PS6's value in keeping the Playstation ecosystem strong is overplayed. If the PS5 (and PS4 to an extent) remain active, then PS6 crashing wouldn't have a huge impact on Somy's gaming business. The link between new hardware and a healthy business is too weak now. The Switch 2 is destroying the PS5 currently, but Nintendo's financials are much weaker. But relatively pro-consumer choices from Nintendo vs persistent anti-consumer choices from Sony may translate to a future where Nintendo dominates them in almost all metrics, it's hard to say where this is going and how much will change even a year from now.
