Just because its the title of the video, doesn't mean its not clickbait, youtube proves that every day a thousand times. The series X isn't "performing badly" at all. Its certainly not underpergorming vs the ps5, considering the multiplatfirm games are very similar to this point. What, we are supposed to be surprised that like 3 multiplaform games rushed out for launch aren't that optimized? Doesn't really prove anything.
Regardless of of the case, right now Series X is not performing as well as it should be. Whatever the exact reason is, right now its a problem.