The filters in the Recent Changes page provide two sets of filters for "User registration" (registered and unregistered) and "Experience level" (newcomers, learners and experienced users) that are closely related. Experienced levels act as a sub-set of the registered filter. This makes some relevant selections impossible to achieve such as viewing at the same time IPs and the registered users with less expertise (as this user comment points out). Although highlighting can be used as a workaround, we can consider whether these filters would work better as a single group.
Providing all these filters in a single group would allow for users to select both "unregistered" and "newcomers" to view edits from users of both kinds. In terms of filtering contributions, it does not present additional limitations, and allows for selections that were not possible before. In other words, the AND-based combination that separate groups provides is useless and the OR-based combination of being in the same group could be useful instead.
In terms of usability we need to identify whether the resulting group is easy to understand as a coherent unit for users.