Deus Ex 3 is indeed an RPG. It's a hybrid action/RPG just like the first game. There is a skill system where you upgrade your character (Adam) based off experience points you earn and you can do the same thing with weapons. It's a game with a very detailed plot with numerous characters you interact with. The gameplay takes the form of a consequence-driven multi-path, multi-solution approach in a non-linear space.
For stealth, that is another major pillar of gameplay and we do have it. The difference is that it's now cover-based rather than "shadow/light-based" as in the past games.