Getting Gold in all Cosmic Missions is really not fair or fun at all.

[Doki]

The OP is saying Expert crafting and gathering is trash game design because it adds an element of tedium that renders completion of the task up entirely to RNG even if you yourself are a master at utilizing the system to its fullest.

And I agree. That's trash game design.

THIS. Yes, I'm aware the majority of the lower missions are trival to do (even BEFORE the new gear). As a completionist I want to be able to finish ALL missions for the achievement without relying on the mercy of RNG to hand it to me when the content is still relevant, not a year later.

Top missions rely on RNG of getting the right status at the right time , complete roll of dice, regardless of skill level.
Or I could go do treasure maps which are RNG x8 x 5.
Or I could do EX trials for a 5% RNG chance of getting the mount to drop and RNG x8 chance of winning roll.
Or I could do PvP modes that are complete RNG of who DF pairs you with.
Or I could RNG bid on a house.