They create the constant and you go through it ever how you want. Especially in the open world.
You want to storm the keep. have at it.
You want to stealth in and kill just the boss. All you gamer.
You want to fly in and pick and choose your targets. all you.
You want to RP it. Have at it.
You want to get through it as quickly as possible. Thats the gamers decision.
You want to view every encounter till max level as a speed bump of worthless content and do nothing but raid. Enjoy.
blizzard taking away flying cause they can't be bothered to balance flying or design content with flying in mind shows a massive lack of ingenuity and creativity.