a backtrack wouldn’t make any difference if the reason for the delay was wake.
The reason for the 2 minute delay was not wake it was same track separation. The point is, had they remained at the intersection the 2 minutes same track separation would've become 3 minutes wake turbulence separation. Note, I am not saying that is what happened, I am just saying it is a perfectly plausible alternative to the crew being "idiots who don't understand performance".