Most people would say that, especially those who just look at the stats from the surface. But when you actually look deeper, you will see that Barkley was the better player. By better, I mean that a team should pick Barkley over Malone if it was starting from scratch.
Malone was fantastic with a phenomenal PG, we know that, but we don't know how he would fare without one. We sort of know what Barkley could do with an all-star level PG (Kevin Johnson), but as good as KJ was, he was no Stockton when it comes to creating offense for his teammates.
I couldn't find the points assisted stats going way back in the day, but I am positive that way more of Karl Malone's points were assisted (as a result of the pick and roll), while Barkley created most of his own offense. The downside is that Barkley was a low post pound the ball kind of guy, who tends to stop the offensive flow of a team, but Barkley could create offense as well as anyone in that era.
Barkley led the league in True shooting percentage for four straight years, which was phenomenal for a big man who doesn't shoot a lot from 3, take into account that those were the 6ers years when his teammates were horrible and the entire opposition was strictly to stop Barkley, and this is even more amazing.
Malone once led the league in offensive win share with 12.1 in the 97-98 season. While Barkley never led the league in offensive win share, he 3 seasons of 13+ from 88 to 90 (that is during the Jordan gone nuts years and Magic Johnson's prime and Barkley finished #2 in all three of those seasons).
Malone, with his longer career, obviously had a higher career win share (just like playing longer gave him more points that Jordan while Jordan had a higher PPG average and was obviously the better scorer), but when you look at career win share per 48 minutes, Barkley stood at 0.216, while Malone had 0.205, Malone had a career high of 0.268, while Barkley did it slightly better with 0.269. Despite a shorter career, Barkley had 4 seasons of 0.250 win shares per 48 minutes, while Malone only had 3. Malone had a career high win share of 16.7, while Barkley has two seasons that bested/tied that figure, with a high of 17.3.
Malone was much better defensively, I will give you that, but Barkley simply helped his team won more games. Also take into account that players on better teams usually gets higher win share numbers (sort of like +/-), and Barkley was stuck on some truly horrible teams more big chunks of his career, and you can see Barkley was simply the guy you want to build around rather than Malone.
Also, Barkley was the better rebounder, outside shooter, and passer, and you will see that Barkley has a very strong case of > Malone.
I haven't even taken into account Barkley's performance in the playoffs vs. Malone.