In this case their “stroll” intentionally flaunts custom and tradition.
It is a conscious act daring anyone to react in any way they can call racist.
They do the same thing on sidewalks and in the malls.
Lining up abreast and slowly “strolling” to block the walkways.
I watched the video. Nobody would make a big deal if it was two seconds where someone faces the crowd and waves, or takes a picture with the Dean. But some of those people were off on other parts of the stage, and the ceremony couldn’t go on until they were off.
If they are clowning around up on the stage with some professor and they decide to have the next person go up, is that person going to decide to cut behind the person getting the diploma and ruin their shot for family and friends?
It is, the way it appeared in the video, narcissistic, self-centered, inconsiderate and rude.
One can only imagine how long the ceremony will take next time.