There is not much advantage, it is just additional functionality.
You can add Access Profiles in LCS - Provisioning, you can’t add Roles there. Yo will have some advantages here.
Adding Entitlements directly in Role is a new feature, if you think that why should I create an Access Profile just because that is the only way I can add in Roles, then this is the answer for that.
Let’s say that, you need to have 2 Entitlements from different sources in a Role, earlier you need to create 2 Access Profiles for that, unnecessary objects, but with this new feature, you don’t need to.
You can add Access Profiles in Application, not Roles.