You can pair a hardware signing device with Nunchuk that does have a display (like a Coldcard or Blockstream Jade), and verify the details of the transaction before signing. You can also pair multiple hardware with Nunchukm and create a multisig wallet, which offers superior security and robustness compared to a singlesig wallet.

In the above setup, Nunchuk only acts as a watch-only wallet coordinator. So yes, 100% Nunchuk can be used for cold storage. And many of our users have done so.