If Shaq was shooting 60% is that better than Curry if he's shooting 48% from three.
In 2001 i.e. Shaq's prime, he shot 79.2% from 0-3 feet and took 45.2% of his attempts from that range. His FTr was 68.4% that season and he took 13.1 FT's a game. Even if he drew fouls at the same percentage from all points on the floor (which is clearly underestimating his 0-3 foot shots), that means he took 5.92 foul shots and 8.6784 FG's every game from 0-3 feet. Working the math at 79.2%, that means he generated 13.75 points from FG's and 3.04 points from FT's or 16.787 points for every 8.6784 FG attempts from 0-3 feet or right about 1.93 points for every shot and with a more appropriate FTr, it was likely over 2 points per shot.
Curry has never shot better than 45.5% from 3 (his 3rd season), but for this exercise I will use 2016 when he shot 45.4% though with over twice as many 3's as his 3rd season (so his best shooting season). So at 11.2 3PTA, that means he makes 5.0848 and scores 15.25 points on his 11.2 shots. Now that doesn't account for FT's, which Curry obviously gets on occasion from his 3 pointers (his FTr that season was .250). So even assuming he gets fouled at that same rate from 3 as everywhere else, that means Curry would add 2.5484 extra points. So on Curry's 11.2 3 pointers he scores 17.7984 points or 1.589 points per shot.
So in sum, a Shaq shot right at the basket is worth significantly more points than a Curry 3 point attempt. Now obviously not every shot Shaq takes is right at the rim, but in 01 Shaq scored 28.7 ppg on 19.2 shots or 1.495 points per shot, which is still better than a Curry 3 pointer. And to keep the math fair, that season overall Curry scored 30.1 ppg on 20.2 shots, or 1.49 points per shot. So Shaq still slightly better.
I think people just forget how dominant a true big man is even though we currently have a guy like Shaq in the game. His name is Giannis and he is best player in the world. His FG% at the rim is actually better than Shaq ever had over the last few seasons and Giannis, just like Shaq, shoots over 40% of his attempts from 0-3 feet. Giannis obviously plays more on the outside than Shaq ever did, but what makes Giannis so great is that he is arguably the best interior scorer since Wilt, in a time when people seem to be going away from the interior. But that is still far and away the best shot a guy can take.