This is a custodial-web wallet: your credentials and signing key live on this server, not on your device. A wallet operator that holds your credentials is a new entity in your threat model. If any of the following describes you, this wallet shape is not the right default for you, and you should use a device-bound wallet or wait for an EUDI-class wallet instead:
This is positioning guidance, not a hard restriction; the protocol cannot enforce wallet-shape choice.