For me it seems it's a USB-A problem with the iPhone 16 Pro. First off let me say this: It's not an iTunes problem. If the computer recognizes the phone, then iTunes will. At least that's what I've been seeing on multiple computers. And here's what I have: a Mac Mini and a MacBookPro. They are Intel machines and they are running Bootcamp with both Windows 10 and macOS installed. On the MacBookPro there are only USB-C ports so I'm using a USB-C to USB-C cable (as you would expect) and everything's working fine in both Windows 10 and MacOS. Windows recognizes the iPhone 16 Pro, so does iTunes. On the MacOS side a Finder window recognizes the iPhone.
On my Mac Mini I have USB-A ports and USB-C Ports. When using a USB-A to USB-C cable and using the USB-A port on the MacMini the iPHone is not recognized in either macOS or WIndows 10. When using the USB-C port with a USB-C to USB-C cable the iphone 16 Pro is recognized both in Windows and iTunes and on the macOS the iphone appears in a finder window.
So with what I've found, it seems it's not an iTunes / iPHone 16 Max problem. AND It's not a Windows 10 / iPhone 16 Max problem. The foundation of the problem is that it's a USB-A port problem. When you try and get the iPhone 16 Pro to be recognized on a machine using a USB-A port you'll fail. The only thing you'll see is that iPhone will charge, but that's it. The use of a USB-A port will cause failure with getting the phone recognized whether it's on a Mac or a PC. So, if someone doesn't have any machines with USB-C ports then it seems they are kind of out of luck.