I own a repair shop so I’m sure my perspective comes from spending an unusual amount of time in UEFI/BIOS over the course of the years, but I find that they remain perfectly usable with a keyboard.
Most modern UEFI have an “advanced mode” (usually F7) that is a lot closer to traditional BIOS layout and navigability. I actually get unreasonably bothered when trainees insist on fumbling around with the mouse in “Easy Mode”
There’s so many options in modern UEFI that there are two features I’m actually incredibly grateful for:
The “Favorites” systems, so that you can have all of the settings you’ll actually change all in one place
The “Profiles” systems, so that you can easily hop between configurations
Without those, the onion meta-game of finding options that are arranged differently on AMD vs Intel or between different motherboard vendors is a rough time.