It's no different then 2 people in my guild who always get the rare mount drops while the other 99% never see any after hundreds of runs. RNG is RNG.
- - - Updated - - -
Blizzard doesn't give 2 fucks about the world first race. It's a fictional competition among guilds. Mythic+ leaderboard clears weekly as well. Blizzard added legendaries for the entire player base.
Plus Legendaries don't work in PVP. The trinkets we get from PVP boxes with on-use? Don't work in PVP. Only world PVP. Nothing works in PVP at all.