Your advice is usually spot-on, but I have to take issue with this part of your comment:
On the eMMC models there is QSPI memory which changes when you flash the Jetson. Those changes go beyond just creating a boot image. This also includes what are essentially pointers to devices for booting. The implication is that in an eMMC model, even if you boot “most” of it from an external media (e.g., USB thumb drive), there is no possibility of putting all boot content on the external device. The act of flashing such a Jetson changes the Jetson itself, and not just the boot media you see .
The SD card model of a Nano does have all of this content in the SD card (not sure how the SD card model would work if it has no SD card, but other boot media, e.g., just a USB thumb drive, never tried). Basically this means that all content on an SD card for use with an SD card dev kit can be cloned and different people could have different SD cards which are customized, e.g., different login names, different optional software, but eMMC models won’t have this flexibility.
That’s just not true. The SD-based Nano (SKU0) devkit has a QSPI chip that it boots from, and in later releases (MaxSPI) everything needed to boot is on QSPI, and the OS/rootfs is all that is on the SD-card. On the commercial Nano module (SKU2), it’s all eMMC-based, no QSPI. So both the boot firmware && the OS/rootfs is on eMMC.
So with a Nano devkit (QSPI+SD-card), you can boot different OSes by changing what’s on the SD-card (or USB stick, etc.). And you should update the QSPI boot firmware to the most recent release (32.5+, JP4.5+). Please don’t use older SD-card images (JP4.4 or prior) as that’s a mixed environment and may not function perfectly (as the bootloaders and the kernel/OS aren’t in sync).
Note that your point about ‘no possibility of putting all boot content on the external device’ is true for either Nano module - the BootROM in the T210 SoC will boot from the strapped boot device, either QSPI or eMMC. You can only ever load the kernel, kernel DTB, ramdisk, and rootfs/OS from external media (USB, NVMe, SD-card, etc.).