I've also found the OpenAI image models to lose fine detail on image edits compared to Nano Banana or Flux models which faithfully retain input source image geometry and details. I was hoping this might be different but it sounds similar to previous OpenAI image models where something is lost in translation during image editing.
I know the API (assuming you're using it) lets you set the output size of the edited images - I haven't done a huge amount of testing with > 1mp, so I'd be curious if this might mitigate some of that.
https://developers.openai.com/api/reference/python/resources...