It's a chicken & egg scenario, the missing element for SBD to provide stability is liquidity. Liquidity requires a sufficient trade volume. The invention of "BitAssests" back in the day by Dan Larimer / BitShares was a straightforward application of a derivatives market, BitUSD and SBD are prime examples as are NuBits.
The derivative mechanism is clear, what is needed for it to work is marketing, time and adoption. Perhaps we need to learn patience and how to focus on ease of use and identifying target audiences for specific use cases. When we can do that it's a matter of marketing to reach that audience with a clear message of how our software is the perfect tool to help those users accomplish their goals.