My signature aside, Kubel in the hands of someone with
1000 hrs+ driving time is USF's nightmare yes. It also dies extremely quickly if you make a single mistake with it and becomes a micro tax/liability very quickly too. It prob feels more of a problem when part of combined arms, where it's more a more obvious target than the other infantry. Combined with escapes on low hp, it can be frustrating yes but far far less than almost any other LV.
It has 240hp effective (192 hp with 0.8 received damage modifier). You don't use zooks to counter kubel, you use rifles/LMGs/BARs/just focused fire or even AT guns.
If you want to see an annoying T0 unit, check out the UC. That used to not even have a fuel cost and some ppl considered it fine
That said, USF can't really complain much about health bleed since they have the ambulance.....