Well, for the one at the end, the angles seem odd. We're viewing the three stationary characters from slightly below and the character jumping out from slightly above. Also, I don't watch this show, but does it make sense for the character in motion to be that much smaller than the characters in the background that he's jumping in front of? If not that's a problem.
For the shot the narrator has labeled as "awkward composition" my issue with it would be the fact that Blossom and Bubbles are standing on the bottom of the frame. I don't actually care about whatever those lines are supposed to mean. But I'm also not a nitpicky stickler for composition... whiiiich is where I take issue with this video.
I think the compositions in the original PPG show are great and the style is amazing. Not everything has to be in perspective or three dimensional, so long as it's a mindful choice by the creators. Stylization can really set a show/comic apart and help with the tone. I don't even have a problem with that side face they show in the beginning of the video, because as they said that's an in-between, and also side faces in cartoons and comics are often stylized to allow the characters to emote or maintain recognizability.
Take, for instance, this image of Dexter from Dexter's Lab.

Obviously, this is not what glasses look like from the side. Glasses don't curve around your face. They're basically flat and from the side the arm of the glasses kind of blocks your eye. But does it look bad drawn this way? Nah dude. Because you never would have been able to see Dexter's expression if his glasses were drawn in an accurate to our 3D world way. Also, the perspective of his locker door is off, because the artists wanted to have more room to show the Einstein poster.
I'm getting long winded here, but what I'm saying is, yeah those shots from the new show are awkward, but I don't necessarily think the nitpicking I see on youtube of modern cartoons is constructive or even a good educational tool. I've seen too many of those youtubers miss the point of stylization in favor of perspective and staying on model... which can kind of cut more stylized art off at the knee. But ya know, "learn the rules before you break them" "Eat your vegetables" and all that.