This 15.3% is mostly real staking / lending yield (~14.1% of it). Only about 8% comes from token emissions. It is single-asset, so there is no impermanent loss to drag you below holding. It can still fall, but it isn't a disappearing subsidy.
Real fee/staking yield: 14.1% · token emissions: 8% of the headline.
No impermanent loss here — the ~14.1% is real income on the very asset you'd be holding anyway. Only any emissions portion fades.
Source: DefiLlama. Verdict is a heuristic over public data, not financial advice.