> While this will eventually reduce workload for boot/installation components (grub2 reduces surface area, syslinux goes away entirely, anaconda reduces surface area)
For heaven sake please stop using grub, it's a nightmare. You need multiple levels of scripts/programs to take your confusing human configuration & kick out the verbose complex full grub.cfg, which you then need to run another tool to install onto the drive. It's absurd, it sucks.
Systemd-boot (nee Gummiboot) is just amazing. There's some very very simple text files, on the EFI partition, that you can freely edit, and the bootloader will work with. There's a live editor you can use if things go wrong.
The much loved Pop!OS uses systemd-boot if it detects UEFI. Let that be your guide for what's good for users, I swear, it's so much better. I'm not sure whether I support abandoning legacy boot yet- I hate to just drop support quite so soon, but really, support in hardware has been quite awesome, albeit not quite for a decade yet. But moving to drop legacy support would be a great step, some day, and will make moving to systemd-boot an obvious & vast improvement over horrific terrible grub2.
Hearing that OVH & many many Amazon instances use legacy BIOS is cry-into-your-hands sad. This is like IPv6 transition hard: there's just such a huge userbase that'll never be incentivized to move on. Woe.