The relevant point being that not everybody believes they're a "game of skill" in the "skill vs. chance" slider which is relevant to the law. While there's no question that like every game, user actions (skill) can impact the outcome, how much it can impact the outcome is what determines whether something is classified as a game of skill or chance. Perhaps it's more clear if we say "a game of primarily skill" or "primarily chance".

If daily fantasy sports is primarily skill-based, they can do it. If it's primarily chance-based, it's illegal in the US. Which is why they're pushing for it to be referred to as "skill-based".