Just now I tried tethering from my iPhone 15 Pro Max to iPad Pro M1 12.9". Used TB4 cable, TB3 cable, charging cable (USB2.0), all of them don't work. And yes the iPad did charge the phone but that's it.
The trust this device dialogue did pop up when they are connected. But even inside of the Files app I couldn't get them to see each other.
I don't know if it is supposed to be like this or I didn't dig deep enough. But wired tethering is pretty obvious when plugging an iPhone to a MacBook.