I have seen Scaled Agile Framework (SAFe) work in multiple real program teams. Doing it successfully requires total commitment at multiple levels and many organizations are culturally incapable of making the transitions.
To be clear I am not claiming that SAFe is necessarily the best possible methodology. There is certainly room for improvement. But empirically it can work in real life.
The organizations I've seen do SAFe at the top level "coincidentally" have so much in the way of resources that if they do software at the group level at all, they do it like a gentleman farms.