Russia don't have to be able to win a full-scale war against the EU for such a war to break out, it suffices that deterrence breaks down sufficiently that Russia get the idea they can get away with some land grab, e.g. in one of the Baltic countries.
The war in Ukraine illustrates very well the difference between perception and reality. Perception counts for deterrence.
The Baltics are protected under the EU defence clause, NATO or not they will be assisted by the EU.
It's already quite clear the US has virtually left NATO, at this point they wouldn't assist at all with a landgrab in the Baltics so I'm glad the EU defence treaty is more forceful about the level of aid/assistance than Article 5.
NATO at this point is virtually dead, there's no trust in the USA and the rhetoric about Greenland has cemented it. Hope the Canucks can join a defence pact with the EU, the Trump admin and its Project 2025 achieved what they wanted.
The war in Ukraine illustrates very well the difference between perception and reality. Perception counts for deterrence.