This thread is referencing if the SSD fails. If the SSD fails, the computer won't turn on, and even if it could (which we wish were the case, but the T2 chip prevents), you couldn't use get anything off the disk because it's a dead SSD.

In the event of an OS crash/issue, or just minor corruption, that might be an option. Related to the original article -- I'm not sure what is meant by DFU mode on a MacBook (only have heard of that on iDevices) so it's unclear to me if you can EFI boot into another OS. Given that it also affects Asahi Linux, sounds like you can't EFI boot into anything, even OS Recovery for Mac Sharing mode.