The medallions were an economic tool, instituted during the Great Depression, to regulate a spiraling industry. Whether or not they “should” be valuable is a nonsense framing: they were introduced to enforce scarcity, which makes them valuable. Neither of us has to like them to recognize their outsized value and function in the welfare of a large number of peoples’ lives.

But to the larger point: medallions made NYC yellowcabs more expensive than the market demands, and they’re still cheaper than ridesharing.

Sure. But this is a different claim from the OP’s. Nobody is entitled to returns on investments, but the claim that ridershare apps are either affordable or good for cabbies is farcical in NYC, at the minimum.