The "slave" or "steward" is in charge of or has been appointed over his fellow "domestics." I'm now going to change one word and say exactly the same thing: The "slave" or "steward" is in charge of or has been appointed over his fellow "slaves."
It's very imporant that the word be rendered slave or servant. This is because Matthew 24:45 is an allegorical reference to the story of Joseph in Genesis. Joseph's life path is very important as it led to the position he eventually held, which actually was leader of the known world: Pharaoh of Egypt. He starts out as a boy and then is put through a rigorous childhood of being envied and eventually betrayed by his own brothers.
There are deep truths held in the reason why the story of Joseph was written down the way it was. And those truths are why it is referenced in Matthew 24:45. Jesus is speaking to people who know the Torah well. In communities where the masses are illiterate storytelling is a mix of information and entertainment. The more interesting the story the easier it is to remember. So the art of storytelling was used as a way of educating the masses.
In the contentious verse in the Book of Matthew I believe Jesus was speaking of a time in the distant future. A time where there will be two types of people. The Joseph types, that deserve to be given what Joseph was given: the seat of the throne to the known world and the Anti-Joseph types which deserve to burn forever in eternal damnation. The stark contrast between the two possibilities is reason to believe Jesus is speaking about the distant future a time without grey, only black and white. Joseph, in Genesis, was chosen by Pharaoh to be acting Pharaoh because even the great Egyptian King was merely from a random noble line. He must have at least secretly knew he had random genetic limitations. In all his wisdom he could not gain the experience and passion that was within Joseph because of what happened to him. It was Zaphnath-Paaneah that had a very humanitarian thing going on that was providing food for the house of Israel during bitter famine.
Matthew 5:5 - Blessed are the meek,
for they will inherit the earth.
-Sab