Unable to show "view key" when using ledger hardware wallet

[ghost]

version: v1.8.0

1. create a wallet with Ledger
2. click "show private keys" from settings.

The view key I got is:
0000000000000000000000000000000000000000000000000000000000000000

The spend key I got is:
ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

It's understandable that the spend key should not be exported to GUI wallet, it should only stay in the hardware wallet, no one should be able to access the key, all transactions should be signed by the hardware wallet.

However, it's surprising to me that the view key is 0. Ideally, it should be possible to backup or even share the view key to another person/device.

Is that something we could change?

[ghost]

Same behavior from cli wallet:

viewkey
secret: On device. Not available