I don't think there is a way to only disable it for oneself, like customizing and personalizing looks.
However, setting Capabilities/moodle/contentbank:access to Prohibit for each user role makes the Content Bank disappear.
I have only tested it for a short period of time for the role of teacher so use with caution, some more testing might be needed. However, when I tried to access the content bar in the role of teacher by direct use of the URL the expected error code was displayed, so at first glance prohibiting the capability seems sufficient.