Kawhi didn't get 1st-team All-NBA or compete for an MVP until the year he turned 25. Luka just turned 25 last month and already has pulled 4 1st-team All-NBA selections and is in the MVP conversation every season. Luka at the age of 24 already had more 1st-team All-NBA selections than Kawhi did his entire career. And Kawhi did have a great run with Toronto in 2019, but that's literally the only season in his career that he advanced past the 2nd round as a #1.
Luka's career trajectory right now is way ahead of where Kawhi's was at the same age. Shai's trajectory isn't too far from Kawhi's either and is certainly ahead of anyone else in Kawhi's draft class.
My argument is that the actual career accomplishments of the 2011 class aren't that impressive cause several of them had very short peaks. There isn't anyone in the 2018 class that looks likely to apply to. Luka has already made more 1st-team All-NBA teams than Kawhi has, Shai made more 1st-team All-NBA than Kyrie, Jalen Brunson and Trae Young are already better than IT ever was and if their peak is as short as IT's it will be a huge shock.
I'm fine with saying the 2018 draft has potential to surpass 2011, but I cannot elevate them over 2011 until they actually do it. So yeah sure, you can argue that Luka & Shai are on the trajectory to have better careers than Kawhi & Kyrie but trajectory is just potential until it's actually done.