I am not very knowledgeable of the US law but a law websiste² does point out that anti competitive behavior is punishable, a monopoly position is not. I personally would label a lot of things apple does (like e.g. not allowing game streaming from 3rd parties, not allowing the use of other browsers, not allow people to use existing payment infrastructure, ...) as anti competitive.

A layer on youtube³ however says throughout multiple videos that epic has a (if even)very weak case and apple is in the right.

I would be interested to have someone break it down to understand the case.

[2]https://definitions.uslegal.com/m/monopoly/

[3]https://www.youtube.com/channel/UCi5RTzzeCFurWTPLm8usDkQ