Can confirm it does not. You cannot remove the slow via Purge (Support) or Cleansing yourself (Templar) or using Forward Momentum (2H) or Retreating Maneuvers (Assault)
Doesnt really matter if it can be purged or not since we have gap closers without cost stack penalty.
I'm thinking this, plus the availability of other snares, and the fact that some mechanics ignore movement speed debuffs will all combine to make this set too strong.