Aint this what we ask for?

[Shirai]

People asked for long time goals and something that lasts longer than a week.

NO one asked for FATE grinding - No one.

In my humble opinion the FATE grinding is not the biggest issue since there's basically no improvement involved on the weapon itself for that stage.
The RNG part on the Atma drops is the thing that completely kills the moods of many people.

Yes, we asked for relic upgrades to take a bit more than "Kill one mob, collect booty, get weapon", but we didn't ask to be forced to spend an unforseeable amount of hours doing the same thing over and over, hoping the RNG favors you next only to see that other guy that just came in the zone walk away with it.
That guy can be the kindest soul in the universe for all that matters, but at that moment he's an asshole and the game even moreso.

If we're talking about a progress timesink which is thought out well, it's the trials.
There's no real skill involved there either, but they take time to get (1500 Myth) and they cover several activities in this game which can all be done solo, but you can also get friends or other people to help you, if you want.