i would assume that this is not possible. Since CUBA uses JPA it falls under the same constraints. JPA in contrast to something like Hibernate native does not allow something like naming strategies to readjust the names defined in the entity classes (see here and here for more details).
Since CUBA defines the table names in the source code like in the User entity it is not possible to change it. Even the platform possibility to extend platform entities will not change that, because it will adjust the existing table instead of using the name of the extended entity.
But that’s just my two cents. Anyone else might have another idea.