People hold Bitcoin and Etherum because they want to be able to make a profit on it raising in price. If someone sells their Bitcoin to buy Doge and Bitcoin doubles in price they don’t earn any profit. If they however used the Bitcoin as collateral for a loan, the will make a profit if Bitcoin rises in price.
Vitalik’s explanation of how he made $56,803 on betting on Trump losing on Augur would be one practical case of someone using this method.
Just like Vitalik made profit with using the inefficiency in the Augur prediction market other people are likely using the leveraged capital to make money with the above described yield farming.
You predict nothing of that sort in the linked comment. The antibody test being negative is a distinct event from immunization.
You offered 50⁄50 odds for an event that johnswentworth gave 29% likelihood (which was the maximum of anybody giving). It’s quite obvious why nobody takes you up on 50⁄50 odds when nobody has a higher then 29% likelihood of believing that the event happens.