Because the dev now works at Google, he had to remove the root hiding functions called SU Hide. You can bring it back with various modules, but I was lazy and wanted a install one, do all solution.
Magisk Delta is a fork that brings back SU Hide, and I haven't needed to install an extra app to fix any apps it couldn't hide root from.
Oh God. Somewhat unrelated, but I felt like I knew the name "Deimos" from somewhere. Couldn't put my finger on it. Finally realized who he was.