It must have been something of a relief for Anson Mount to have a scene in which his character could speak. I have disliked Inhumans, and I did not really enjoy Black Bolt's character, but I have to recognize that it must be difficult for an actor to be in a show without so much scenes in which you're not supposed to speak and only convey something through your facial emotions.
This scene was an interesting development in both Black Bolt's and Maximus' arcs. I liked how Maximus feels in the end, completely disillusioned, "I am the King of Attilan", trapped alone on the Moon. I sure hope he would take this time to reflect on his actions. A bit like Connors in Cloak & Dagger during his time in the Dark Dimension, or Victor Stein while he was trapped in the Healing Algorithm.
With all the backlash that came with the show, I doubt that we will ever see Maximus or the other Inhumans again.