While you're complaining about the super easy every 36 hr, 2-3 hours a day leve grind for a 50 in about 4-6 weeks
those of us that are 50 and have killed every NM a few dozen or more times, are finding ourselves having nothing to do but
level other classes that we neither need actions from or care about.
Honestly, if there is no 50 content then no one has anything to look forward to, or any reason to bother leveling to 50

End game content gives those that are lower rank something to look forward to, and gives those that are there something to do other than wait for some word of reason to return to the game
Middle and low level content only gives people enough reason to level to that range, and drives away the players that have nothing to do at max level. You can't honestly say that you would be hapy with a max level character if you had absolutely nothing to do. Had nothing to gain, and making money or leveling crafts was completely pointless because you have all the best gear already.