Importing iPhone 15 Pro Max photos to old Mac OS gives black garble images

[boredandlonely]

I had seen this answered on a different site months ago, and I fixed it, but now the problem returned and the solution post is gone. I want to say the answer had something to do with camera settings on the iPhone, but me toggling things isn't finding it.

I'm importing camera images taken on and from an iPhone 15 Pro Max, running iOS 17.x, onto my High Sierra "Photos" app. They keep importing in the Photos app looking black garble (see sample pic).

1. How do I stop it on the iPhone?
2. How do I fix existing camera roll images so they import normally?

Thanks in advance.