After surpassing Ray Allen, Warriors guard Steven Curry officially became the NBA's new all-time three-point king, and Ray Allen's 2973 three-point record for many years was surpassed. Since then, Curry will continue to set new records. But for Ray Allen, he may be surpassed by more people in the future.

On the NBA's all-time three-point list, the Nets guard Harden, currently ranked No. 4, is likely to overtake Ray Allen in about three years. Currently, Harden has hit 2,509 three-pointers, 464 three-pointers away from Ray Allen.
Over the past few seasons, when Harden played for the Rockets, he has shot more than 200 three-pointers in a single season, such as the crazy 378 in the 2018-19 season. Last season, he played for the Rockets and nets, where he shot 121 shots (only playing 44 regular season games) due to injuries and a decline in the number of shots to the Nets.
If Harden can play more games, he will not have a problem shooting 150 three-pointers in a single season, which also means that Harden is likely to surpass Ray Allen in about three years.
Among active players, lillard (2114) is behind Curry and Harden in three-point shooting, who is 859 short of Ray Allen, who has shot around 200 three-pointers in a single season since entering the NBA in 2012-13, and at least 270 in the past two seasons. Although the feel has declined this season and the constant rumors of trading have led to ups and downs in performance, Lillard can still surpass Ray Allen in about four years if he plays normally.
The active player behind Lillard is The Lakers' James, who now shot 2,023 three-pointers, 950 short of Ray Allen. Since James hasn't shot too many three-pointers, no more than 150 three-point shots in a single season in the past season, and he's almost 37 years old, it may be difficult for James to surpass Ray Allen in the future (at least more than 6 years).
In addition, George, Klay Thompson, Durant and others also have a chance to surpass Ray Allen, but except for Tang Shen, the other two are not players with a particularly large number of three-point shots, so they all need more time.