Earlier quoted context omitted.
Too late to edit: non-GPT, non-MBR For instance, whole-disk btrfs. Or old BSD partition schemes.
How much benefit would there be in whole-disk btrfs? The space taken up by GPT and the FAT32 EFI partition is a rounding error compared to the sizes of modern disks.
I am not the OP and I do not do this. However...
Yes, the disk space used is a rounding error and one far right of the decimal point.
But there is extra space used in the human brain that sets this up.
Instead of `/dev/sda1` it's `/dev/sda`. Instead of `/dev/nvme0l0p1` or whatever (I own almost no NVMe kit) it's `/dev/nvme0l0`. And so on.
This could be helpful; I can certainly imagine it simplifying things somewhat.