This entire tournament is a brand new meta on a new patch that completely changes the way that teams are playing the game. Valorant is a game where meta is incredibly important in deciding the strength of a team, and shifting away from the tejo/breach meta forces teams to come up with new and untested meta calls, and to play the entire game in a different way than before.
This is likely why some of these teams look out of sorts right now, as they have had to shift their entire playstyle and adapt to the meta in a matter of a few weeks. Obviously, this doesn't completely excuse a terrible showing like the 13-1's that we've had the past couple of days, but it is still a huge factor imo.