Not OP, but the facts are that while Russia is rapidly exhausting its military hardware (which can be independently verified), Europe has relied perhaps too heavily on the US defense industry for military hardware and capabilities. This works fine when there is a good relationship with the US, but does not work when regime change occurs and the US takes an adversarial posture with its supposed allies. If your friend no longer offers to equip you for defense and war, you should be prepared to build your own. Otherwise, you've already lost.

Russia isn't going to win, it's going to slow burn to failure (again, military hardware exhaustion, parts of their economy on the brink of failure, working age demographics crisis leading to ~21% central bank rates to attempt to quell inflation to no avail), but Europe improving its military capabilities would derisk against potential tail risk aggression and losses as Russia stumbles to a failure mode. Putin will die eventually, although it is unknown who and what replaces him; Europe must manage that risk.

Europe is learning the hard way that you can't use economics to tame an aggressor (Nord Stream) nor can you rely on benevolent allies to be benevolent in perpetuity. This is objectively good, as it will force Europe to re-industrialize to an extent, and I argue manufacturing base and supply chains are of national security interest (gestures broadly at everything). Not your manufacturing base and supply chain? Not your freedom.