I'm not sure if my 2016 MacBook 12", on Mojave, is affected by this or not. The IP shows as successfully changed in ifconfig, but not in the Network Preferences > Advanced > Hardware area. Is that normal?

My specific laptop aside, here are the other discussions I found on this, in case this helps:
https://github.com/feross/SpoofMAC/issues/87
https://github.com/halo/LinkLiar/issues/33
https://forums.developer.apple.com/thread/106768
https://www.reddit.com/r/macbook/comments/93h2mi/mac_address_changing_on_new_2018_mbp_broken/