A founder here still playing on and off...
It is unfair, because first most of the outfits in this game are timed gated or limited. Granted, most of the outfits do come out again once in a while.
Secondly, with the Master Pack (where you get the Transcendence outfit from) it was stated that it was only for that pack and will not be obtainable again.
Taken from here: https://www.bladeandsoul.com/en/news/founders-pack-last-chance/
"In addition to the basic benefits and bonuses, the Master pack also includes costumes and weapon skins that are exclusive to the Master Founder’s Pack, and will never be obtainable again."