Germans keep complaining about the loss of Russian gas and refuse to see the war as an opportunity to scale up their military industrial complex, arm themselves to the teeth, sell weapons to Eastern and Southern Europe. Poland and Romania are buying tanks and howitzers from the US and South Korea, the French have their own industry.
Rheinmetall has been increasing production though. It's just a) getting into this business is hard, so it has limited effect on the rest of the economy b) arming oneself to teeth costs money, which is German budget is pretty low on at the monent
A leopard 2 costs about 30 million euros, how much of that is spent on energy you think? It’s just ridiculous to claim that energy is the bottleneck here.