If I understand this correctly this is not about not giving Ukraine munitions it is about not giving the EU money to buy munitions to give to Ukraine. Each country in NATO is sovereign and pays for its own military. Each nation gives equipment and ordinance to Ukraine. There’s no change here (apart from the US saying they’re no longer supporting Ukraine). For the EU the future pooling resources will be developed within a sovereign framework so giving money to the EU for equipment now is like removing military sovereignty. Given that military procurement is rife with corruption and inflated costs, and the EU have no framework, or military strategy, or mandate for a EU army, you can understand why countries are reluctant to give money to the EU rather than giving to Ukraine directly.