It is exaggerated. Schrecks have been on Volks since ever and OKW was regarded as one of the weakest factions in 1v1 before the patch. And out of all things people are complaining about they choose the freaking Schreck on Volks argument, disregarding the stuff that has actually changed. You are complaining about symptoms, not the reasons. Make the Shreck upgrade cost 150 munitions then, go on.
even while the okw had clipped fuel and munition income, schreck spam was one of the most reliable strat OKW had access to.
Now the OKW can schreck spam in additional to using all of their toy freely because of the increased income.
The increased fuel should have encourageed the okw to build and use more of their vehicle, but instead people just default to OKW's most tried and tested strat : schreck spam.