I don't think there is anything wrong (not just morally, but pragmatically, too) with posting, discussing and preparing for TEOTWAWKI scenarios among Catholics, as long as there is some balance. If living in the Faith - prayer life, Mass (if you're able to assist at a real Mass), the Sacraments, etc - is not neglected or hindered, and a person's mental health is not adversely affected by these apocalyptic thoughts, then I don't see a problem with it. I don't disagree with the other posters' comments on this thread, but I think it's a little presumptuous and unfair to think that those who prepare for, and discuss, apocalyptic scenarios are lacking in their spiritual lives and relationships with Christ. However, I do admit that I've sometimes gone a little overboard with such posits about TEOTWAWKI scenarios. Hark, although Christ told us only the Father in Heaven knows when Christ returns, He also told us to keep watch. Moreover, the Apocalypse of John was given to us for a reason, so we - with eyes to see and ears to hear - might know the signs and prepare for the coming events.
To Bishop Williamson's credit, at least a few years ago (not exactly sure when), he did foretell the events now occurring in, and against, Russia in this . He basically states how Russia will be painted as the "boogeyman" (my words) by the West in order to galvanize support to target them with an imperialist campaign, whether it's military (just look at what's been happening in Ukraine and Syria - proxy warfare), cultural (the West painting Putin as a tyrant for criminalizing public fαɢɢօtry, fruit marriages and insults/mockery towards the Church), etc.; and Bishop Williamson states how Moscow might just be the 3rd Rome, and how Russians are undergoing a return to the Faith, although, they are not there yet because they are not Catholic. There might be more that I can't remember off the top of my head, but it's in the video linked to "interview" that's underlined above...