In terms of casual content, bfa had more group activities. Islands and warfronts were the 2 main casual group activities. The nearest SL has is boreghst but that’s a poor replacement. Boreghast is comparable more to visions. Except visions had a lot more stuff going on in them than boreghast does. But both borrghast and visions weren’t/aren’t really casual content anyway. Especially at higher levels.
So what does the casual have left? Callings? No thanks. There’s a reason why most people in bfa stopped doing emissaries after a while.
I guess we’ll see what future patches have in store. But thusfar there really isn’t that much content once you’ve completed your covenant campaign. I suspect that is ultimately why there’s been a massive sub loss.