GT was the perfect opportunity to bring in an extra bowler
I don't think there will be a change in batting intent any time soon. But reading the pitch, assessing the conditions (if they even do that) and the history of the ground should have warranted bringing in an extra bowler on a bowling friendly pitch.
Madushanka or Coetzee in place of Head would have given more responsibility to the batsmen when there isn't an extra batter like always. We know they can score 200s and 240s with Head in the lineup, but this could have given the batsmen an opportunity to build partnerships and play responsibly, just for a game. Cuz you know where the finals is going to be and you just know that Siraj, Rabada and Holder (all Test bowlers) aren't bowlers you can put pressure on early by playing T20 shots and not play the ball on its merit, especially on that wicket.
If you think this isn't the time for experimenting with the lineup, I suggest recalling the finals of 2016.