Kali Live boots on anything. Other distros don't. What makes it unique?

I have become a fan of Kali Live, not for the tools, rather for it's ability to boot on every device that I have tried.

I would like to be able to boot a very small/fast distro like BunsenLabs Lithium on the slower/older/tablet devices but my understanding of the boot process is (apologies) seriously lacking.

*Kali live boots and is usable but can take up to 5 minutes to boot on the older/slower devices.

What makes the Kali Live boot process able to boot on anything, even devices that won't boot any other distro?


Background:
Longtime Linux user, Developer skills: slightly above zero

I am tasked with maintaining many devices across many different organizations. I frequently need to pull images from broken devices and then write the images to replacement devices. Kali will boot on any of them (as long as secure boot is disabled) and has been a lifesaver.
Most Frequent: Surface Go, Lenovo Tablets, Dell Tablets, etc.

Concerning the tablets, Kali Live USB will boot on any of them, whereas other distros won't boot on any of them.

I have tried the following distros via unetbootin, etcher and rufus:
SLAX, PEPPERMINT, Q4OS, Puppy, Porteus, LXDE (LXLE), LUBUNTU, Linux Lite, BunsenLabs Lithium, antiX, Linux Mint, Zorin, Gentoo. Bohdi.
The only other distro that will boot on some tablets is Manjaro, but it isn't as reliable as Kali Live.

I suspect that the following has something to do with it but I can't find any documentation/how-to's that I can use to dig in and figure this out.

Kali Live USB Live fdisk -l output:

/dev/sda1 * 64 5755903 ........ Hidden HPFS/NTFS
/dev/sda2 ........ Fat12
/dev/sda3 ........ Linux (Persistence Partition)

As opposed to BunsenLabs Lithium 'USB Live Fdisk -l

/dev/sdb1 * 204 190085143 ........ W95 FAT32 (LAB)
/dev/sdb2 ........ Linux (Persistence Partition)


/dev/sda2 is a 736K , Fat12 partition containing the boot files but is not flagged as bootable.

/dev/sdb1 is a bootable partition for Lithium but contains similar files etc, compared to the Kali Live /dev/sa1 bootable partition.

the /Kali Live /dev/sa1 bootable partition starts at 64 whereas the dev/sdb1 bootable partition for Lithium starts at 2048.

Any light you can shed on this will be greatly appreciated. Thank you!