Here is some relevant information that came up in the Artix forum
https://www.phoronix.com/scan.php?page=news_item&px=Xorgproto-Debut-Release
It seems as a whole bunch of proto files were replaced by this combined file this past week
The question is what is libxfont and libxfont2, it seems as the first was orphaned by xorg-server and the second is the new dependency. But that is in artix, probably something that slipped past the pkging but came up as a conflict to some people when xorgproto appeared. Maybe irrelevant to arch and obarun.