My just for fun conspiracy theory, (Not meant to be taken seriously)
The way I see it. SE decided that there would be a "choke point" on relic, so that they wouldn't blaze though the steps quickly. Previously that choakpoint was Atma, but since they needed to keep players around so that the game remains profitable they decided to move it, so they devised a clever scheme.
- Increase Atma rates (seems simple enought but since SE still has to keep the tedium aspect, a later step to be made harder
- So they implement a DPS class, the first new class since the relaunch, That fact alone would cause massive hype
- Players, consumed by the hype, clog the DF with Rouges and Ninja making Animus take just as long as Atma was initially and also moving the RNG aspect to that step
- But Dungeons were just a small aspect of the Animus quest And those that already have it would be unaffected they have to slow Novus down too. The way they did was simple, slow the alex gain, by making it harder to gain Alexandrite they make the road to nexus slower