I watched Threads five or so years ago, but it was meh, maybe it hit harder if you watched it decades ago. This, on the other hand . . . gave me pause, as a grownass man: https://www.youtube.com/watch?v=4cAZZR_Jki0
Yes, that was pretty heavy as well. And it is much more likely now than when it was first distributed. What they really got right there is the degree of uncertainty that accompanies almost every statement. You never really know what is going on other than that things are escalating, quickly. And that leaves you wondering all the time what the real situation is, and then the next update makes you realize it was worse. This feeling never really leaves you.
It actually seems less likely now. Russia didn't have the military strength to invade the other European countries but we didn't know until they bashed themselves against Ukraine. Back when the current war started analysts seemed to be predicting it would be over in days or weeks.
The nuclear side is still scary but the idea that Russia would even try to engage NATO forces and then have a showdown seems ludicrous.
Kinda like 9/11, when no one fully knew what the hell was going on in real time other than it was very, very bad, except substitute the less than a handful of planes being hijacked with civilization-ending nukes flying all over the place.