I think they would struggle a bit more in today's game.
The speed, size, and agility of the average player is much greater today than it was in the 60s. Plus, the physicality of the game has increased considerably. That doesn't mean they'd be anything close to "average" - but I don't think their stats would be as gaudy as they were in the late 60s with today's rules/gameplay.
No one in the NCAA has averaged 30 ppg over a season since 1997 (30.1), and only two have done it since 1992. By contrast, from 1955-75, only one scoring leader dipped below 30 ppg (to a paltry 29.5).
Was curious to see what might have caused the dropoff, so I looked up the NCAA rule change history.
Looks like 1972 had some significant changes.... free throw was eliminated on the first 6 common fouls of each half (rescinding a rule from 1957), and refs were given the ability to call fouls away from the ball for holding, grabbing, and illegal screens. Then in 1982, the 5 second rule was instituted for a closely-guarded player. Then in 1985, the shot clock was introduced. And in 1986, the 3 point shot was introduced
I think the changes from 72-85 benefited the defense quite a bit before the advent of the 3-point shot. How many of Maravich's points came off of what today would be considered an illegal screen? How many of his points came off of free throws on common fouls (looking at his stats, he shot a lot more free throws than anyone shoots today), or after being face-guarded more than 5 seconds, or after the shot clock would have expired?
Those players would still be tremendous talents... it's just that the gap between the elite and the average has shrunk a bit more today than it was 50 years ago, and the rules in place today would limit them a bit more than they were. Maravich might be in that 28-32 ppg range, rather than the 44-45 ppg range, for instance.
