Coldcard is designed around a threat model most wallets ignore: someone has your device, or your computer is compromised, or you are being forced to open it. Dual secure elements from independent vendors mean compromising one chip is not enough. Air-gapped operation over microSD means the device need never connect to anything.
The features that matter
Duress PINs open a decoy wallet with a small balance; brick PINs destroy the device's secure elements permanently. Passphrase support allows hidden wallets that leave no trace on the device. Partially signed bitcoin transactions are constructed on a watch-only wallet such as Sparrow, moved by microSD, signed offline and moved back. Nothing about that flow requires trusting a cable, a USB stack or a host computer.
What you give up
Bitcoin only. No Ethereum, no tokens, no NFTs. The workflow requires understanding UTXOs and PSBTs, and the interface is a small screen with physical keys rather than anything friendly. If you would find that frustrating, the device will not protect you from the mistakes frustration causes.
Who should use it
Bitcoin holders storing meaningful value long term, particularly anyone building a multisig quorum where geographic and vendor diversity matter. Pair it with Sparrow Wallet. For multi-chain use, a BitBox02 or Keystone will serve better.