But we can say that if Marissa Mayer (and others at Google) hadn’t worked more than a regular 40 hour week, they most likely wouldn’t have had success at the level they did.
So broadly you can say # of hours impacts success and is therefore meaningful depending on the quality of your output. When Marissa says ‘130 hours’ she’s just stating a supposed fact. She’s using that number to simply show the massive effort she and others put in.
Also, do you think professional athletes for example, train without thinking about # of hours of work they need to put in to achieve X? It’s certainly part of the equation.