How Detroit's bankruptcy could be solved and also lead to more freedom, but Democrats will fight strongly against this

So what would be a legitimate argument against selling off this property?  Why does the Financial Times think that this is so outlandish?  Don't people think that it would be nice to get a large amount of money to pay off some of the city's debts?  From the Financial Times:

Among all the helpful suggestions the Motor City has received during its slide into bankruptcy, selling off Belle Isle, a picturesque island park in the Detroit river, to a group of billionaires intent on creating a libertarian city-state ranks among the most outlandish. 

Yet Rodney Lockwood, the local property developer who has been pushing his idea for a “Commonwealth of Belle Isle”, is not alone in imagining there is value locked up in city-owned assets, which could be put up for sale to help pay creditors. . . .