Apple - Image Capture takes a long time to import and convert photos and videos from iPhone to MacBook
iPhone settings -> Photos -> Transfer to Mac or PC -> Switch from "Automatic" to "Keep Originals"
There's also a "Keep Originals" option in the OSX Image Capture app, I'm not sure how the two options interact with each other. From my brief testing, if the box is ticked in either place then imports will be super-fast and you'll get the original .heic images instead of the converted .jpeg ones.