According to ESPN.com's Zach Lowe, Jefferson said he and the rest of the 2016-17 Cavs were confident in their superiority over a non-Durant Warriors team: "I know we all believe—and it's just our opinion—that if Golden State brought back the same team [in 2017], we would have dominated."
After falling to Golden State in the 2015 NBA Finals, the trio of LeBron James, Kyrie Irving and Kevin Love led Cleveland to its first NBA championship in 2016, when it beat the Warriors in seven games.
As a result, the Warriors made a big splash by signing Durant during the ensuing offseason, and Golden State went on to beat Cleveland in each of the next two NBA Finals.
Cleveland fell to Golden State in five games in the 2017 NBA Finals, and Durant's dominance was a big reason for that. He was named the NBA Finals MVP by averaging 35.2 points, 8.2 rebounds and 5.4 assists per game.
James put up 33.6 points, 12.0 rebounds and 10.0 assists per contest in that series, but the Cavs were unable to overcome Golden State's Big Four of Durant, Stephen Curry, Klay Thompson and Draymond Green.
The Cavaliers were even more overmatched last season following the trade of Irving to the Boston Celtics. Golden State swept Cleveland, and Durant was once again named NBA Finals MVP, as he averaged 28.8 points, 10.8 rebounds and 7.5 assists.
Durant joined an already great Warriors team that had reached two consecutive NBA Finals, and he essentially made it unbeatable over the next two years. Even a Cavs team with three All-Stars of its own in James, Irving and Love couldn't compete in 2017.
Now, the Cavs are one of the worst teams in the NBA with Irving in Boston and James playing for the Los Angeles Lakers. Meanwhile, the Warriors remain atop the Western Conference at 45-21, and they are once again favored to go to the NBA Finals.
Golden State's stranglehold on the West could be nearing an end, though, since Durant can become a free agent and depart during the offseason.
The Warriors will likely still be a top team with Curry leading the way should Durant opt to leave, but as the Cavaliers showed in 2016, they are more beatable without Durant. That could be even truer now with strong teams such as the Milwaukee Bucks, Toronto Raptors, Philadelphia 76ers and Celtics emerging in the East.
Golden State is the closest thing to a dynasty the NBA has seen since the '90s Chicago Bulls teams led by Michael Jordan and Scottie Pippen that won six titles in eight years, and Durant's arrival is a big reason. If not for that, Jefferson and others who were part of the Cavaliers organization are of the mindset that the dynasty could have existed in Cleveland instead.
Had that been the case, it could have changed the balance of power in the NBA, and perhaps it would have influenced LeBron's free-agency decision as well.