What is the difference between PSBT support in Coldcard and Trezor? The 10x Security Bitcoin Guide says that the only two hardware wallets support BIP174 (partially signed Bitcoin transactions, or PSBT). However, this Reddit thread says that &quot;You can use PSBT with Trezor via HWI&quot;. This Github issue elaborates.
What is the difference between the level of support of PSBT between Coldcard / Cobo and Trezor? Should a user care?
The Coldcard handles PSBT directly and natively. A PSBT can given to the device by writing it to a microSD card and inserting the card into the device. It will be able to load the PSBT and process it as a transaction. Additionally when communicating with the device over USB, PSBTs can be given directly instead of being packed into another data structure.
However other hardware wallets like the Trezor do not have this capability yet. Instead these must be given transactions over USB and those transactions must be packed into device specific data structures. The HWI software does this translation for users - it takes PSBTs and converts them into the format that each hardware wallet uses.