If if if if if if if ifHe's looking at results...
Harden Houston playoff averages - 28/7/6 - EFG 49.5 - 42/32/87 shooting splits. (if you include OKC/Philly/Brooklyn it gets much worse)
Doncic playoff averages - 32.5/8/9 on 52.7% EFG - 47.3/36.6/69.2 shooting splits... this is as a 20-22 year old.
Also... Harden was real close to winning a title... if his team didn't fold (17 straight missed threes) or CP doesn't have terrible hamstrings he may have won a ring. Doncic's game goes up a notch while Harden's goes down... sometimes by a lot. Its not symptoms of a bigger issue... its results. Luka is here for the pressure... James is not.
It's like being the 100% focal point of your offense and deciding to argue with the refs more than you play transition defense makes you less likely to win the games that matter.