I have pretty much the exact same setup, and I do get a video feed.
Is your Mac connected to the same network both through Wi-Fi and Ethernet at the same time? If so, try turning off Wi-Fi on your Mac and see if that helps.
Thanks for that information. It is good to hear that it works in principle.
Maybe it has to do with the settings for the NDI encoding on the iPhone? For example, if the data rate is set too high, it may not transfer any video. You could also check in the NDI Access Manager to see what prefered protocol is selected:
Maybe you could try “Reliable UDP”. I noticed that sometimes “Single TCP” from the popup works better. I think this depends on your network configuration.