The Goldman link says that the overtime rules will add jobs. I agree.
My comment was addressed to the $15 minimum wage, not the 40-hour week. The Goldman link does not address that at all that I could see.
Why will the $15 minimum wage eliminate jobs? Basic supply-and-demand economics. When the price of something goes up, the usage goes down. (Unless you can make labor a Veblen good, where the high price increases demand. But that depends on status signalling. You could think about trying to make that apply to labor, but I think it would be rare to have cases where that worked.)