They only show the lead-up and follow-up of the oral-rape scene with The Deep and Starlight. We don’t need to (or want to) watch the actual encounter because the important info is what led up to it and how Starlight reacted; the audience wouldn’t gain anything additional by watching the actual act.

However they do show the scene where The Deep gets gill-raped, because it’s weird enough that the act itself needs to be shown to be understood by the audience, and watching The Deep’s reaction to what is happening while it’s happening is important (the pain, the powerlessness, the confusion). Starlight realizes what is happening before the rape itself; The Deep only realizes while in the midst of it, because as a man/abuser he doesn’t expect to be on the receiving end of what he’s been remorselessly fishing out (autocorrect turned dishing into fishing and I’m leaving it).

The sex scenes between Stillwell and Homelander are weird and uncomfortable, but a respectable implementation of show-don’t-tell of their complicated Oedipal relationship (as we learn that during intercourse Stillwell treats Homelander like her young child, presumably as a calculated way to control him and secure the loyalty of an incredibly dangerous loose cannon). Given the theme of a child raised without a mother, and Homelander’s eventual murder of Stillwell, I accept the artistic decision to include scenes of their intimacy so that the audience better understands their bizarre relationship.