Earlier quoted context omitted.
The lending rates are higher because lenders are paid a premium for owning a potentially worthless (USDT denominated) credit. The idiom that comes to mind is "picking up pennies in front of a steamroller".
It flips back and forth with USDC, which one is higher, at least on compound.finance. Right now USDC is higher, but it's been different. Here are the historical charts (click the "borrow" tab, doesn't seem to be a way to link it with that one selected): https://compound.finance/markets/USDC https://compound.finance/markets/USDT For example, on October 7, it shows USDT at over (sorry, "north of") 13%, while USDC was (…
The demand for Tether comes mostly from Binance and the other centralized Asian exchanges. The demand for Circle dollars comes from the DeFi ecosystem and FTX.