I don't want to sound overly optemistic here, but if the DM UI for this is AAA quality, Sigil could do a lot to close the DM shortage gap. For one, if it intuitively handles most of the combat bandwidth for DMs, making it much easier, that's one huge benifit. And if the dungeon designer UI is equally great, I can see how a generation who grew up plahying Minecraft could get entranced with creating enviornments for themselves and others to play in. IE, if it's a JOY, rather than a chore to build dungeons, what might we see being created.
This could be the 'streaming live play' boost for this decade of D&D.
Edit: Spelling error for Minecraft