Islam critiqued seeks marriage counseling; Satisfying many wives in your 50s?

In answer to the video "Muhammad did it. Therefore it is not sinful."

The prophet Muhammad, like many eminent prophets of the past, had a large household towards the end of his life. With such a large household combined with his prophetic duties and the turmoil of these early days in which he was involved in on a daily basis, he could not be expected to divide his time so as to satisfy each of the wives and potential concubines equally. But as the Islamic history books explicitly denote, he tried to observe equality among them as much as possible. He used to visit sometimes his 9 wives at once.

In that report, the Arabic doesnt denote sexual intercourse, on the part of that humble man in his late 50s who had in addition to balance his household duties with his extraordinary responsibilities as a spiritual leader and statesman. Some of his male companions might have assumed so, but it did not have to be the case. And to further corroborate that the prophet, despite visiting all his wives, would only have intercourse with the one whose turn had arrived

"Narrated ‘Urwah: ‘A’ishah said: “O nephew! The Messenger of Allah would not prefer any one of us to another with regards to spending time with us. Hardly a day would go by without him visiting all of us. He would come close to each woman, without touching her, until he reached the one whose turn it was, then he would spend the night with her".

The flexibility of the law as regards the division of time is of course not speaking of the sustenance and rightful material needs of every wife. In this area, the prophet had to divide his resources among every household, in addition to the financial burden of taking care of the indebted of the community and the incessant guests who would be received at all moments. He is known to have been left with very little to spend on himself and his wives, leading to them often complaining about the relative ease in which other companion's wives were living. And this at a time where the community had grown more prosperous in Medina, an ease which was not reflected in the prophet's household 

33:28-9"say to your wives: If you desire this world´s life and its adornment, then come, I will give you a provision and allow you to depart a goodly departing".