I don't like equating a fielder's quality directly to amount of catches taken/runouts effected.
It's like that scenario where you compare two batsmen, Batsman A who averages 25 and Batsman B who averages 30. If the value of a Batsman was all about runs, Batsman B wins, but if you factor in that Batsman A opens the batting and reliably sees off the new ball, while Batsman B scores his runs from down the order, then it isn't so straightforward. Seeing off the new ball gives the rest of the batsmen to come a better chance of scoring runs, and can compensate for the lack of runs from Batsman A himsels.
Likewise, Jonty's simple presence in the field in that point region had several knock-on effects that benefited the side. Batsmen were less willing to cut the ball in the air, for example. If they cut it along the ground, they would have to hit it fairly wide of Jonty in order to beat him. This often meant finding the sweepers in the deep. This made the cut shot -a productive shot for many batsmen- suddenly a no-go. This allowed the SA quick bowlers escape with a few short and wide balls during their spells, thus easing the pressure on them and enabling them to bowl better. It also added pressure to the batsmen, since a scoring area is now cut off. This forces them to find runs elsewhere, creating more mistakes.
Point is also a great reigion for lots of batsmen to find singles against quick, hit-the-deck bowlers. It's also where the ball often flies to if you miscue driving a wide outswinger. SA's quick bowlers were mostly either hit the deck bowlers, or bowled quick outswingers. Jonty made them all more potent.
So yea...Ponting had more catches and runouts per game. But that doesn't mean Jonty's influence on the game is any less. Ponting fielded in attacking areas, places where catch and runout opportunities presented themselves, and capitalised on the batsmen's mistakes. Jonty fielded primarily in a run saving position, which in ODIs made him incredibly valuable, and in Tests meant that the batsmen found it harder to find a release against his side's bowlers. It's not easy to pick who was better for the team's cause.