How much have The Last of Us, GTA V or so, so many other remasters sold this gen alone? How many have been made? How much has the Super NES mini sold? People are still interested and invested in those games.
Sony has two options: either lose the (lots of) money that they make off of that market or allow Microsoft PR to slash them over making you buy again the same games. Unlike many here, I'm not so sure they'll go with option 1, but so far only Sony knows and any comment saying "they'll certainly have BC" is nothing but wishful thinking at this point. But to say that these games don't interest people anymore... that's like denying climate change.
It's true that Ryan made those comments about BC at a different time and it's just PR talk. But it's also true that if they intended to include BC on PS5 it'd have made more sense to say "we don't think this is how we want to approach this issue, we have PSNow instead, but we are always listening to the fans' feedback". That'd have been PR talk too, but it wouldn't have created unnecessary shit storms if they were planning BC eventually anyways.