I can still read “”Do not leave butter at room temperature for more than 4 hours,” says Engen. “Always return any unused butter to the refrigerator and be aware that butter left outside refrigeration may become darker in color and have [its] flavor affected. “ You may have to read through or have someone read it to you to make sure i didn’t make it up.
Nowhere does he say it is no good after four hours as you said.
He only said color and taste MAY be affected.