Trials of the Braves (which, yes, includes farming ATMA stones) Part I
I realize that it is not possible to make everyone happy, really I do. I know it is a constant challenge for developers to keep things new and interesting and difficult for the hard core raiders, while providing adequately interesting and amply rewarding content for the casual players. Game developers have always sought to slow progression (why I don't know, but I accept it as part of every game I have played to date.)
Your game, to date, has done this extremely well compared to other games I played (Everquest for far too many years for one lol) in that you can get up to current content level and gear at a fairly decent rate, and casuals are not lacking compared to the hard core raid type players.
However, this relic upgrade quest has been atrocious in just the short time since release. I realize the flack you are getting is disoriented and angry, but that is born of the absolute frustration we as your player base are suffering at the moment.
Part II (seriously only 1000 characters!)
1. ATMA stone drop rates are completely random in that not every fate grants one, and the person getting it when it does drop is completely random as well. So, someone who has done every fate in the zone and got gold (some people are not getting gold and I don't think they realize that they had zero chance when that occurs) 8-10 times are still waiting for a drop, and someone zones in, joins their group, and gets it on the first fate, because RNG is random!
Possible resolutions: Tie it to completing every fate in a zone with gold even the rare spawn fates; Keep the fate that drops one random but give it to the highest contributor of that fate; Tie it to the completion of 100 fates in a zone with gold.