Here’s the link to the german interview where he said it, though it’s not translated. Ion’s liked posts about it on twitter so the interview’s legit.
Here’s what it says using Google Translate anyway, with a few things corrected:
But there are a few specializations that we want to touch. This includes, for example, the Subtlety Rogue, because it has moved a lot in the direction of shadow magic and teleportation in recent years, and this no longer corresponds to what you think of as a WoW Rogue. We may be moving more towards control, sneaking and the image of the PvP archetype again.