“Last year, European old masters generated $594 million of auction sales, just 6 percent of the global total, according to a report published by Art Basel and U.B.S. This modest percentage is surely set to rise after that Leonardo price. But will it have any effect on the wider market for historic pictures, particularly since the “Salvator Mundi” was not offered in a mainstream sale of old masters, but, incongruously, in an evening auction of contemporary art?”