Mcmahon tournament groups

What is the method used to make groups in Mcmahon tournaments?

In this tournament the bar is set pretty low at 10k. Below the bar the groups seem normal, above the bar it should be random? though it doesn’t seem so?

Or am I just seeing patterns into a random process as we humans tend to do?

Initial pairing method is set to Slide, not random.

how does that work?

Slide pairing (a.k.a. cross pairing)

Done by dividing the group of players, ordered from strongest to weakest, into two strength ordered sets, one containing the stronger players of the group, the other containing the weaker players of the group. The strongest player of the stronger set is paired with the strongest player of the weaker set. The next strongest player of the stronger set is paired with the next strongest player of the weaker set, till all players have been paired or there is only one player unpaired.

This method also aims to have the strongest players play each other in later rounds, to produce exciting games at the end of the tournament, but tries to avoid the disadvantage of giving the top players a bad SOS due to their first round pairing.

Slide pairings are especially popular in the first round of Swiss tournaments