This post gives great insights into how a soft peg actually works. it's all depending on what point people start seeing value in buying DEC to buy in-game assets. There's no point in buying DEC at 1000 DEC ~ 1$ to buy in-game assets because you won't be profiting at all. So depending on other factors, like the prices of in-game assets on secondary markets, the real peg definitely lies below the value of 1000 DEC ~ 1$.
If people would stop believing that it's profitable to buy DEC for buying in-game assets, I don't see anything stopping the price from going down.
Anyhow thanks for the great read!