Currently, I don't think there's a way to restrict rows or button visibility in a "grouped" manner, based on the active login. The only available option is %username%
For rows, you can at least set security per-user, e.g:
But this can get tedious and hard to manage.
Button visibility doesn't appear to even have %username% as a Compare Field option.
It would be nice if other fields in the designated User Profile table were available to use for this. That way, you could for example add a "Department" column to the User Profile table and set security/visibility in bulk, instead of by individual username.
I see there's an open feature request for controlling visibility via AD groups, which would be great. But I thought this could be an alternative, potentially easier-to-implement approach.