> They already enforce other practices top down like hiring etc, so if they had data saying that mandating Scrum would make the company X% more efficient they would absolutely do it.
lol, as if their top-down hiring practices are at all driven by concerns for company efficiency.
Why do you think otherwise? The whole reason they do it is that they looked at other big companies and noticed that everyone ended up with mediocre workforces after a while, so they did this to avoid that scenario. Then as they grew bigger they could hire a lot of data people to analyse different methods and see how well different things works to optimize further. When you spend tens of billions on engineering salaries at a data driven company you will do that.