I cursory read the FAQ, somewhat funny that it's a series of questions with a "no" answer, that made me curious about the author, so I looked for public speakings on YouTube. Right now the first hit is a 18 minutes presentation of this book (so I think as I haven't watched it yet) called "(sixth RacketCon): Matthew Butterick -- The Making of “Beautiful Racket”".
I thought that someone else here could be interested...
It never crossed my mind that LVM and similar needs utilities to access the filesystem and to be honest, I thought initrd/initramfs contained only kernel modules, not executables and scripts... ^__^;
You can ditch the initrd if you compile in the kernel the drivers you need to boot the system, as a minimal example SATA/SCSI, EXT4/JFS, that usually are compiled as kernel modules.
I thought that someone else here could be interested...
edit: clarifications