Best value in gaming - oh wait, that only counts for subs. Oh wait - there's a sub too. Nevermind.Since pretty much all PS4 games are also PS5 games so people who skipped last gen are starting with the combined library of hundreds of games. That's a great value proposition for new buyers.
/s - seriously though, for BC consoles, when 90% of active userbase is on new console (which usually happens within first 6 months of new launch), you can take it for granted last-gen software is being bought primarily bought by new console users.
Not that PS4 software has been charting much in Japan either - but still, it makes the numbers a bit different.