43% shooting was not efficient, but he was 40% from 3, he was a rookie, compare to only rookies. 16 ppg and shooting 43/40/84 shooting is good for a rookie pg. He played out of position, his defense was awful, still not good, but when ONLY comparing to other rookie seasons, he had a good rookie season, which is especially tough on a bad team, because advanced stats favor better teams even for individuals.
Rookies are almost NEVER positive impact players....they are fucking rookies. You said he had a bad rookie season. If you want to say he wasnt a good impact player his rookie year, that is fine, but its also kind of stupid. Rookie players are not positive impact players, they are still learning, we expect too much from rookies, seldom are they ever good. Some dont appear as bad, like a Kobe because he played only 15 mins a game, he shot 42% 37.5 from 3. But Kobe didnt have a bad rookie season, he was a rookie, still learning the league.
Not sure how you think Sexton had a bad rookie season. Sexton wasnt a good player his rookie year, but for a rookie he was better than average. Advanced metrics are garbage without context, and i am a metrics guy, you are just using them to the point that they become useless. Context = Rookie year.