Because there are no requirements to join alliances atm lol. I think it's a good thing that they revive RME. At least it gives something to do, not just staring at the log in hope you get to join a n-th delve boss run from which you don't need anything anyway [because you only need to kill them once right SE ?]. The only alternative would be the release of adoulin versions of ultimate weapons, which they failed to do so far. Also far game balance you can not put a single KI drop on par with the hundred of hours that building a RME cost. If you don't want to spend hours farming your weapon that's fine, you still have the delve boss weapons - they 'll come second most likely.

Someone tell SE to fix the riftcinder/dross supply because it's a headache. Level 99 empy are definitely harder to build than mythics atm. They need to tone down the difficulty of Ig-alima & co because right now it's impossible to low man (I didn't try a lot though, as even at 3M, buying rifticinder for our second level 99 DDB/GH bard was the fastest still).