Is AX88178 compatible without 3rd party drivers? Plugable says no, and IIRC I needed a driver that never got updated for my gigabit ASIX, but it might been a slightly different chipset...
At any rate, a big issue is that for USB, macOS only has generic ECM and NCM drivers. ECM as a protocol sucks and was barely suitable for 100Mbit, let alone gigabit, plus Realtek's implementation of ECM is quirky to say the least.
RTL8156 implements an NCM endpoint, so that's probably the best USB option these days.
At any rate, a big issue is that for USB, macOS only has generic ECM and NCM drivers. ECM as a protocol sucks and was barely suitable for 100Mbit, let alone gigabit, plus Realtek's implementation of ECM is quirky to say the least.
RTL8156 implements an NCM endpoint, so that's probably the best USB option these days.