When running this command:

/give @p gold_ingot{display:{Name:"{\"text\":\"Gold\",\"color\":\"gold\",\"bold\":\"true\",\"italic\":\"false\"}"}}

It gives a gold ingot that has a gold coloured custom name, is named 'Gold', which is bold and is not italicized. Hovering over the item in the inventory shows the correct formatting, but selecting the item in the hotbar does not display the correct formatting and still retains its italicized version even though italic is false.