To their credit, this is a more challenging than your standard Linux distro. Lots of software just has a bunch of subtle bugs on arm which don't exist on x86_64. Other software has a bunch of subtle bugs on 16k page sizes. Those problems aren't ones you'll face as a distro maintainer for some x86_64 Linux distro. Then there's the issue that Arch Linux ARM is itself not always super competently managed, so it's not a solid foundation to build on top of.
I think it'll be very good for them to leave all the distro responsibilities to Fedora and focus on the hardware specific stuff. But I don't think they'll stop facing weird issues related to not being part of the 4k page size x86_64 monoculture.