In short,
Leodis, the banks behave just like any prudent individual, use technology as much as one can but never have all your eggs in one basket, and for some things paper copies are important to keep.
WW3? The increasing number of European countries proposing some form of "voluntary" military service concerns me and I wonder how long before Starmer dusts off Sunak's last election proposal on those lines? So one could say that the likes of France and Germany are getting themselves better prepared for war. But war won't happen while President Trump is engaged in trying to find a compromise between Russia and Ukraine.
The problem is that for most of the time since WW2, western and now increasingly central and eastern European countries have been committed to what is often referred to as a rules based world. But Russia (and numerous other countries of which Iran and China are the most significant) haven't. We say "Russia can't rewarded for its aggression"; absolutely right from a rules based world view. The Russians, not being committed to that view, see it differently.
For all his narcissism and need to be thought right all the time about everything, one of President Trump's virtues is that he understands Putin's point of view, and that ultimately Russia will take control of as much of Ukraine as it wants, unless the US stops it. And the last thing President Trump and probably most Americans want is involvement in another major war. Hence President Trump is trying to broker the best deal he can achieve and knows that de facto if not de jure Putin won't settle for anything short of some territorial gain and a guarantee that Ukraine will not join NATO. Against the rules based world view that goes against the grain, rewarding Russia's aggression. But if the Ukrainians and "Europe" don't accept that, distasteful as it is to those of us who support the idea of a rules based world, sooner or later President Trump will disengage. If then "Europe", meaning in this context principally the current British and French leaders, provide Ukraine with long-range missiles that can hit Moscow, another European war seems to me to be a distinct possibility.