You're being paid 0.66% to absorb price risk. Only ~0.66% of it is real fees — and they stop covering impermanent loss if USDC-BIRB diverges more than the pair moves.
Real fee/staking yield: 0.66% · token emissions: 0% of the headline.
The real fees here (~0.66%) can beat holding if USDC-BIRB stays calm, but a sharp divergence flips that. It's a genuine short-volatility bet, not free income.
Source: DefiLlama. Verdict is a heuristic over public data, not financial advice.