1. Order book, aka enough liquidity, aka moving positions doesn't incur a haircut on your capital.
2. Funding rate stability. aka it doesn't cost much (or actually make you money) to hold the position.
3. Claw-backs, aka you don't wake up one day and find that half your collateral is gone because the market made a big move. This is a big problem especially for Okex.
Basically, a synthetic USD is good if it behaves and yield like a real USD.
BitMEX isn't going through all this trouble and criminal indictment avoiding KYC because people using it are super on the up-and-up and have no problem with validating their identities.
The large majority of synthetic USD trading is speculation and hedging. It's significantly cheaper to trade synthetic USD than actual BTCUSD, so 100% of traders will prefer that.
2. Funding rate stability. aka it doesn't cost much (or actually make you money) to hold the position.
3. Claw-backs, aka you don't wake up one day and find that half your collateral is gone because the market made a big move. This is a big problem especially for Okex.
Basically, a synthetic USD is good if it behaves and yield like a real USD.