I am interested to know how much was the locked bitcoin amount? Please don't say it's 1 or 1/2 mBTC :-D
You guesstimate might actually not be that off, as I see that Binance offers measly ~0.3% apy on bitcoin.
Having said that, I just don't understand why would anyone with their right mind risk holding their bitcoin for such a low return. I mean, I could somewhat understand if we were talking about 5-10% (even though that is very risky too), but 0.3%??