That's tame compared to what they pulled in Diadem. Each instance could RNG spawn a giant instance fate that pretty much needed everyone in it to be coordinated to be able to complete it. At the end of the fate that failed most times, 1 person in the instance would receive a weapon that was 5 levels higher than the best raid weapon at the time. That weapon would be for a random class and would have random stats on it. 1 person in the whole instance of hundreds. And odds that it would be for their main class, with decent stats on it were like the 7th layer of RNG.

Either way, I really hope that SE gets it through their heads that instance designed around grinding against RNG are not fun.