Seriously, there's more to history than just WWII and directly related events.
It all goes back to popular culture. Questions about WWI & WWII, the Middle Ages, and Rome and Greece pop up constantly, and it's not hard to figure out why. How many movies/shows/games have been made about WWII in the last 15 years? How many about Rome? I'm convinced that Game of Thrones alone accounts for much of our medieval interest, and it's not even set on Earth or in the Middle Ages; if anything, it's a weird quasi-War of the Roses setting, and thus early modern.
You might enjoy some earlier posts on the topic
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I feel the answer is because its mythologized image has clear "good" and "bad" side unlike most of other cases where both sides can be accused of being somewhat "evil" (modern Americans probably don't think Vietnam was necessary and just war, just as Russians may be resentful about Afghanistan, but both remember WW2 as heroic great war). There are also many controversies there so it's a big playing field for second-opinion bias like "the real evil were Allies/USSR", genocide Olympics, "all the work was done by USA/USSR", "Hiroshima is as bad as Holocaust" etc.
World War Two is often (very wrongly) seen as a clear-cut good vs evil confrontation, it also in many ways was both the first and last war of its kind and it shaped the contemporary world more than any other major event by ushering in digital computing and nuclear fission. Additionally the sheer scope of the conflict and the fact that it took place very recently makes WW2 the most appealing historical subject for the general population, judging by the constant release of WW2 books, movies and video games every year, it's clear to me that the second world war will continue to generate massive amounts of attention in decades to come.
Seriously
Do you seriously need to ask why there is a great deal of interest and curiosity surrounding the most destructive and widespread conflict in history, the sequence of events with unparallelled influence to our social/political/cultural spheres and direct personal relevance to billions of lives?
there's more to history than just WWII and directly related events
So what? Nobody is obliged to care about this or that just because it happened. Be the change you want to see, get out there and ask some non-WWII related questions instead of making useless spam threads about WWII questions (ironically this thread is 25% of the WWII-related threads on my AH frontpage).