Mostly unable to boot when [ ***] A start job is running for... FOREVER!
Solution 1:
The problem relates to EFI.
Here is an incomplete solution, but enough that I can debug further. I can get it to boot by blacklist EFI modules and disabling ACPI. That is, I need this:
module_blacklist=efi_rts_wq,efi_call_rts acpi=off
I found these hints at CPU soft lockup on Samsung Notebook 9 Pro | Reddit.