Which links further to a blue post having done maintenance reducing queues if you read further. We already have one such discussion thread about queues.
Blizzard has never limited either realms as monofactions.
Edit: To stress the point; both factions are welcome on both realms. Please join the Hardcore train and the niche section of this game whenever you please. Mind that only Nek’Rosh at this moment has no queues at prime time when making your choice.
At 1900 CEST the queue was about 35 minutes~