Because LFR Raiding and non-mythic dungeons exist? It's worked in the past, why is the only way to move forward to remove the casual nature of things? I play FFXIV and I like playing with random dungeons, raids, and trials, and it's to advance without having to have a dedicated group or a super intense focus.

They do an incredibly poor job expanding the content. The only thing expansions provide, aside from occasionally requiring the relatively trivial act of learning slightly different class mechanics, is progression content.

That is, content that provides new/better gear, more challenging fights, etc. That is: content that heavily rewards a hardcore from day one play style.

They consequently are in something of a race against time: the current game is hostile to casual players, who quickly give up and leave when it takes hours to find groups for leveling, and stale to hardcores that “beat” it quickly.

So one can intend to play casually or hardcore and be poorly served in both cases.

The thing is, those aren't "Raids", "Dungeons" or "PvP" - they're specific forms of them. You could run dungeons every day, do a fair amount of raids, and a lot of PvP and be left behind because you aren't doing rated PvP or Mythic+ Dungeons.

There's not even a "You'll have to put in a lot more time." It's just a lockout.