Put it like this, I agree with you both.
You and I have a ton of games that we agree on that we like as our taste in single player games is similar. I don't disagree with where you are coming from, but PS has such a massive install base not solely based on its single player which it does fucking awesome btw, but because someone who like Fifa, Madden, COD, Battlefield, Fortnite, PubG, Back 4 Blood etc. It has the massive install base as it might be one of the heathiest install base in gaming. You have small indies, you have massive AAA Single player, but you have massive AAA MP, you have lots of JRPG etc something for everyone.
What
clarky
is trying to say with lighting in a bottle is that some, if not most MP titles are deeply gameplay focused to the point where the feel and movement of some titles become so legendary even without that series, you don't see a successor, as in even with some of the biggest MP series, they are struggling to even get the sales, of a title...IN THAT SERIES, that is how hard that concept is. We are never going to get some Golden Eye, Halo 2, Smash Bros Melee feels type thing unless its like a Sonic Mania type thing, even with stuff like Halo MCC, when its gone...its gone, even just doing a remaster and remake doesn't mean that past install base will return.
This shows just how hard that concept is if even a fucking remaster can't meet those massive sales, look at COD4 remaster, exact game, better looking, less sales then current COD.
So Battlefield at my age is the only series I actually play for MP titles, I'm done with 99% of that genre lol I mainly play SP titles and just like you, God Of War, Horizon 2, all of that is reason enough for me and anything else is secondary, but that simply isn't enough in terms of the bigger picture.
They indeed will need to fill that gap as they did rely on COD deeply as why put in a marketing deal? Why move your own games away from those releases to give them room to sell more? I'd argue Sony paid for that deal, instead of Killzone or Resistance or something as COD just moves more units and gets better results for their money. Clearly it means something to Sony as a business to do this.
So Clark is correct, this isn't easy and Sony has struggled a lot in the past with this concept and hopefully that new game being made by ex COD developers is able to fill that void and level things out for them genre wise. I don't play much new MP titles in terms of new series, but I'd be willing to try that out.