I think you're incorrectly replacing "role player" with "3 and D" in your head.
Like MCW is a role player. He provides defense and energy. Augustin is a role player, he provides shooting (except this year), Birch is a role player, he sets screens and defends.
Role players operate in specific roles doing 1 or 2 things. A 3 and D player is a guy who can hit threes and defend but you actually have to do those two roles to be considered one