The convenience outweighs the risks for the vast majority of users. My parents need something that is available on all devices, syncs automatically, and requires no maintenance.
You get a master encryption key that never leaves your device when setting up the account. Anything that touches their servers is encrypted with that key. You need that key to setup a new device (in addition to your username and master password).
You get a master encryption key that never leaves your device when setting up the account. Anything that touches their servers is encrypted with that key. You need that key to setup a new device (in addition to your username and master password).