The 2017 Finals marked the first Kevin Durant won an NBA championship during his first season with the Golden State Warriors. KD joined the Warriors from the Oklahoma City Thunder in a controversial move that wasn't well-received around the league.
Durant demonstrated he made the right decision to join the Warriors when he won his first ring against the Cleveland Cavaliers of LeBron James. Even though people considered that move a weak one, Durant achieved what he wanted with the Dubs, defeating everybody on their way to the Finals and having no competition against the Cavs.
LeBron James was still considered the best player on earth at that time, but for some Cavaliers staffers, Durant totally dominated Bron during the series. Ethan Strauss wrote in his book 'The Victory Machine' the reaction of some staffers to Durant's performance during that series.
"When I talked to Cavs staffers about the 2017 Finals, they were upfront about how KD had outplayed LeBron. One went so far as to tell me, “Kevin Durant kicked LeBron’s ass. He completely dominated LeBron in the series. Every time KD needed to score, he did and it didn’t matter what the fuck LeBron did. I was amazed coming out of that series that there wasn’t far more discussion of, ‘Has KD supplanted LeBron as best player in the world?’”
KD dominated the Cavs the two times he faced them in the Finals, winning two Finals MVP awards in the process. He had a purpose; he joined Golden State to become a winner and he did so. You can criticize him all you want but KD achieved what he wanted to achieve. Furthermore, he did so dominating LeBron, his nemesis in the league.