DAI is not something that is meant to be held as an investment to earn money in my opinion. It is a place to park money when you need stability short term. The backers then take your crypto currency risk. If ETH goes up you lose, if ETH goes down you gain. Vice versa for backers. Until something can replace USD as the world currency it will continue to be the preferred option for pegging to. Currently crypto can easily swing 20%+ in a day. As of yet we are not even remotely close to seeing that happen to USD. Once DAI is on a major exchange it will be a very usefully tool to hold between trades just like people love to use USDT even though they should have very little reason to trust Tethers value.

Really the ideal peg would be to the average cost of a unit of labour. In the end that is all currency is, a way to trade one's labour for goods.