The first line contains a PARTUUID, which is an indicator of a GPT-partitioned drive, and the ARM platform does not support the legacy x86 BIOS — the firmware is always going to be some variant of EFI, and on more recent devices, UEFI.
Those are not the duplicates the OP is referring to. The first and the third line both specify that /boot is the mountpoint. The difference is that the first line does it by way of a PARTUID and the third line by way of a filesystem LABEL.
It’s because the Sith Lord Darth Poettering ordained it so when he conceived systemd-mount.