The developer of Blocknet actually said i n a video that he has spoken to another dex called DYDX and he would really like to incorporate margin into a DEX. The future should be 100% decentralized open source margin trading.
I actually have some idea of how this could be done. But I encourage you to reach out and advocate to developers to check out projects like DYDX and Blocknet.
Margin trading on DEX is really a new idea, but I think it does not help much for investors. because DEX does not have too many investors there, so margin trading will not work because investors often focus on large exchanges like Binance, Bitmex for high liquidity.