A lot of it has to do with dedicated servers, but players’ impatience is another aspect of it. Everything needs to be easy, everything needs to be NOW and any opportunity to connect and bond with other people, either as adversaries or as teammates working towards a similar goal, has been replaced.
Of course, my reflexes are too, um, glacial now to make me competitive in any online games like Fortnite, COD, or others, so those huge worlds are the places I go just to hang. I also play Diablo 3 when a new season starts for like the first month. Enough for me to get my main class pimped out pretty well and get near.