...did you actually even read the post? Because that's part of the complaint. One of the game's selling points is being able to play all "classes" on a single character, except you actually can't at the higher end, you're locked into whichever job you decide to gear first.
And no, making an alt for every job you want to play is not a solution. At that point it's just flat out worse than WoW's, ESO's or Guild Wars 2's class system, because those atleast give you some variety while you grind to max level.
Not to mention that almost all cosmetics, mounts and minions are limited to a single character, including those you pay actual money for.