Looking forward to the day when there’s only one layer, multiple ones is a world pvp buzzkill.
you think you do but you don’t 
how are you gonna level when 2000 people are crowding the same zone
questing? a distant memory. your only means of getting experience is to grind mobs. but even then, just tagging one mob per 10 minutes becomes an olympic feat of mastery. and resource professions? lol. don’t even think about it. imagine 50+ people camping EVERY known mining/herb spot.