This is not a bad technique in the Clean & Jerk and the Snatch video. Of course if the time goes by and the athlete is becoming more tired the quality of the technique will maybe decrease. But belief me, if Mitch (snatch video) would not use his hips and would rather use more strength in his arm & shoulder, he would not be able to do 205 reps. in 10 min. at the snatch with just one hand change!

Unlike hard-style, which is more strength oriented, GS involves equal parts strength/endurance/willpower. One of the main goals here is to avoid fatigue / efficient work to save energy to stand the competitive time of 10 minutes.
GS, being a sport, also has ranks based on the size of the kettlebell used and the amount of reps in one of two events:

“Biathlon”: total number of jerks in 10 minutes plus total number of snatches in 10 minuts = your score
“Log Cycle ( Clean and Jerks)”: total reps comleted in 10 minutes=your score

Also the Girevoy Sport is presented among others by big organizations like IKFF, WKC & AKC. The GS-Technique is successfully performed and teached by world famous kettlebell athletes like Steve Cotter, Valery Fedorenko or the russian kettlebell champ Ivan Denisov.

I hope this gives you a different point of view!

With best regards
Sven