While Polymarket does offer holding rewards interest, it looks like it doesn't for this particular market.
That doesn't mean there aren't other explanations. It could mean that No holders expect to incur an opportunity cost greater than the risk free rate. Combine that with how there's low liquidity (there's less than $300 on the book buying Yes, and at 2 cents or less), and so we could just be seeing the effect of random fish temporarily distorting the price. It could also mean that the risk of a smart contract failing is making it not worth the hassle for a market maker to come in at such a slim margin and low volume.
They're offering interest on roughly a dozen hand-picked markets, according to their documentation. (I wasn't aware of that, so I stand corrected on the general assertion that they never do.)
> That doesn't mean there aren't other explanations.
Why do you need other explanations, when the observed probability can be precisely and fully explained by opportunity cost?
I don't have to "need" other explanations in order for them to exist. The current price does happen to accurately reflect what the risk free rate would imply. But look at the graph history: it hovered around 1% for a large chunk of December.
