Possible bug with RLS

mork what you're experiencing is actually the expected behaviour and atleat what I would expect. When you decide to implement RLS you're saying you want to restrict access to data within that report and so that means from that point on any user you want to share this report with you have to explicitly put them under a role in RLS. If you want user to see everything then you leave DAX filter empty for that role but you have to add them to a role. I would consider this as a good design becuase imagine if you had a user that you've shared report with but forgot to add him to a role and so now he is able to see everything within report even though you have RLS implemented.

Hope that make sense.