This was all linked in the article:
While this will eventually reduce workload for boot/installation components (grub2 reduces surface area, syslinux goes away entirely, anaconda reduces surface area), the reduction in support burden extends much further into the stack - for instance, VESA support can be removed from the distro.
[...]
UEFI is required for many desirable features, including applying firmware updates (fwupd) and supporting SecureBoot. As a standalone change, it reduces support burden on everything involved in installing Fedora, since there becomes only one way to do it per platform. Finally, it simplifies our install/live media, since it too only has to boot one way per arch. Freedom Friends Features First - this is that last one.