Malware Resistance
The 2PC(-MPC) eliminates single points of failure for the private key. This means a compromised user, server, or network can at most suggest a transaction to be signed that the other party must approve for it to actually be signed...
Compromised Human Wallet Server​
In the case of a compromised server, the user must also be compromised to steal any key or sign transactions.
Compromised User Device​
In the case of a compromised user device, the server must also be compromised