Are the ALL_OBJECTS and DBA_OBJECTS different when you have DBA Role?
First let's define ALL_OBJECTS and DBA_OBJECTS in oracle:


ALL_OBJECTS describes all objects accessible to the current user.
DBA_OBJECTS describes all objects in the database


As result if you select everything they are different because there are multiple levels of DBA privileges on Oracle. For example if you have SysDBA privileges then you have much more access than a normal DBA.