By the way, re grub detection, once you expand the use case to cover everything possible, here's what is actually roughly required:
Detect all bootlloaders, grub, lilo, and whatever else is used on unix/linux.
handle uefi, which requires all permutations of that possible setup and data sets.
locate root partition, check that partition for boot loader.
locate drive id, like /dev/sda, query that. Query all other drives located to discover all other boot loader instances.
Since the main bootloader can be on another drive, and boot the partition either using the partition boot, or a direct connection to the kernel image thing from the primary grub/lilo whatever, the possibities are somewhat staggering, and would require learning exactly how all types of uefi boot implementations can be detected and handled, all types of boot loaders, all partition and main boot sectors, etc. Scary stuff. My experience with inxi is that once you expand the features to cover most possible scenarios, you're talking about a minimum of 2 weeks of research and development, followed by at least 2 more weeks of fringe case handling and issues. In other words, it would be a major feature, not a trivial thing to do, so I'll wait for a patch for the get_bootloader_data function, I'll handle the print bootloader stuff because it's very picky and hard to understand.
Patch would need to include all possible scenarios, raid boot, uefi, all boot loaders, multi disk systems, systems with multiple instances of bootloaders, etc. I suggest filing an issue report on inxi wiki, it will stay up a long time but might at some date be done if I feel the need to actually have that data, just as the ram issue report stays until it gets done one day.
<update> I created this issue on the wiki, but don't hold your breath, it could be years, or never, but it is an idea so might as well put it somewhere it will remind me now and then.