Probably because at the time Dune was written, people conflated those things in a way that caused a lot of harm to people not interested in harming children. Seems highly reasonable not to feed a trope like that.
It seems to me that that catholic priests abusing choir boys or the "bacha bazi" practice in Afghanistan are still shocking everybody.
However this movie has been made in 2021. People who fail to make the distinction today are few and far between, except maybe in the extreme Christian Right or Fundamentalist Islam. Somehow, I don't think those are the target groups for the movie or book.
IMHO the filmmakers wanted to "protect" (if you allow me such an expression) the "cause" of homosexuality by using preventative narrative censorship. However, a trope cannot be fed if next to nobody understands it in that way, under that specific context. Most of the audience would completely gloss over his homosexuality. Even homophobes are "used to it" now.
This is precisely why I think they did a disservice to the work to pander to modern virtues and little gain. The audience/readers are supposed to find the Baron to be the most execrable human-adjacent being they have ever heard about.
The author wanted to drive us to despise him. In only watching the show, you are robbed of the necessary substrate for that emotion to arise. His evil was abstracted.