mrangry,
In a swept wing (low aspect ratio) aircraft the angle of attack at which you fly results in far greater variations in induced drag than with a straight wing. Therefore, variations of overall energy during a looping manoeuvre are far greater in a swept wing aircraft than in a straight wing one. Because of this and the nature of the lift-curve at high angles of attack, it is far easier in a swept wing aircraft to pull up for a loop and fail to achieve the gate height. Rigid application of gate height protocols are essential for downward looping manoeuvres in a swept wing aircraft but are not really relevant to low speed, straight wing aircraft that have a high pitch rate at the apex.
In short, yes, it is very relevant that this accident occurred in a swept wing aircraft and, commensurately, previous swept wing aerobatic and display experience is also very relevant.