Why would anyone support this knowing how it went the last time? Eric isn't in this because he want you to have a better watch, he is in this so he can sell you out at the first opportunity. It may not be FitBit or Automattic this time, but that's just what he does.
Secondly, he has said that he's trying to build an enduring company. And thirdly, he has said that he's building these in part because he wants to have a watch for himself. That aligns incentives and means that there will be ongoing manufacturing.
Lastly, he has gotten all the software open sourced, which means that if he closes up shop in a year, then anyone else can come in and build a competitor.