****WRONG**** For some the game is PVP. For some the game is increasing their power and raid logging. For some the game is competing in mythic+ dungeons. For some the game is collecting transmogs, mounts, toys, and pets. For some the game is playing the auction house and making as much gold as possible. For others the game is the story.
This is an MMORPG, with so many different paths you can take to get your fulfillment from the game. Is PVP required to play the game? No. Is bolstering your collections required to play the game? No. Is improving your player power required to play the game? Depends on the path you take, but in most cases yes. Are quest storylines required to play the game? Depends on the path you take, but in most cases no. Does the questline from Bolvar increase player power? No, therefore it is not required, and thus ****OPTIONAL**** like everything else in an MMORPG.