So Will Smith’s character believes, but he’s wrong.
Such a plot device could be used to show that no one that the main character encounters seems to have a clear idea of what is going on, and that there is a lot of confusion, panic, and misinformation, and that the city/state/Federal authorities are powerless or MIA.
Plenty of reasons. A large one to support the perception of uncertainty and limited info, which, in an odd way, adds ot the verisimilitude of the story.
Allow me to give a non-cinematic example. The Chronicles of Narnia has a omniscient narrator; the Lord of the Rings does not. As a result, LOTR has a greater feel of being a real history than the Chronicles does, because many times in CoN we receive info that could not possibly have been communicated to a writer except by the writer’s invention. (I’m thinking specifically of the latter third of Last Battle, but there are many more. Contrariwise, LOTR pretends to be the assemblage of many documents and interviews, assembled by a chronicler who was not present for the events in questions who does not know the answers to every possible question. Thus we get an account of the origin of trolls, for instance, from Treebeard, who, though very knowledgeable, is not the narrator and not omniscient, and whose account is not entirely reliable. No account we get in LOTR is entirely reliable, not even coming from Gandalf, and that is intentional; it’s meant to be like life in that regard.
The problem with that fanwank is it makes no sense in context.
Obi-Wan: Is it a fast ship?
Han: Fast ship? You’ve never heard of the Millennium Falcon?
Obi-Wan: Should I have?
Han: It’s the ship that made the Kessel Run in less than 12 parsecs. She’s fast enough for you, old man.
They’re clearly talking about speed, not navigational prowess.A more plausible wank is that Han was tossing around bullshit to impress (and mock) the country rubes. Obi-Wan, of course, saw right through it.
Well, they’re being chased by gun-wielding thugs all the way to the airport in Shanghaim so it makes sense that she would get onto the plane with him (the chief thug also says at one point “shoot the girl too, I can get another”).
Also, wasn’t it the 1930s - would it be considered acceptable for Western women to travel alone through India? (although that’s pretty weak - Jones meets many women who are more forceful and independent than the standards of the time would indicate.)
Here’s a simper one. Maybe, in Galactic pilot jargon/slang, ‘parsec’ is used for ‘parsec per hour’ (or minute, whatever,) just as todays sailors use ‘knot’ (nautical mile) as shorthand for ‘nautical mile.’
Only then, the boast would have been “made the Kessel run in MORE than 12 parsecs.”
After all, no one would boast that ‘We drove to Chicago in less than 60 miles’, with the understanding that ‘miles’ was shorthand for ‘miles per hour.’
Sure, but that’s Earth/Western/US culture. This is long long ago, in a galaxy far far away, with its own culture and norms! 
I believe that explanation involves pilots flying their ships close to black holes while making the Kessel Run, and because the black holes distort space, brave pilots get closer to them and make the run in less distance rather than less time, which makes sense if you think about ohI’vegonecrossedeyedandwhogivesadamnanway.
What should Spielberg had done - changed one of the most famous endings in literature?
I think he was in a serious bind when in came to this movie. If he kept the original ending, he’d be accused of poor screenwriting. If he changed it, he would have faced the same citicism as the makers of Troy - showing disrespect for a classic. In the end, he chose loyalty to the original, no matter how flawed. I find that adnmirable, espicially for a Hollywod filmmaker.
Unfortunately for your analogy, a knot is not a unit of distance; it is only a unit of speed.
In other works a knot is not a “nautical mile.” A knot is a “nautical mile per hour.”
Regarding the much-discussed bacteria-related “plothole” in The War of the Worlds:*
In other words, “Hey, don’t blame me, blame the character!” It seems appropriate that a full explanation of how the Martians managed to know nothing of harmful bacteria, whether they simply never existed on their home world or became extinct in some time immemorial, would be beyond human ken.
Plot hole or not, the death of the Martians was clearly foreshadowed, one might even say telegraphed, by the death of the “red weed” earlier in the story, so it was hardly a deus ex machina.
*ETA: I’m only discussing the novel here. I haven’t seen the recent film and I don’t remember exactly how the explanation was handled in the older one.
Ummmm . . . no.
Remember the Germans had the Arc and it was Belloq that convinced them to open it before they opened it in front of Hitler. Even if it made it directly to Germany, Der Feuhrer’s face would not have melted.
But how does the woman know? She doesn’t, she merely guesses:
“So those machines, that means they’ve been buried a long time, right? So who’s driving the goddamned things?” : pops in tape :
What bugged me is how at least one of them was “buried” conveniently at the center of a major intersection in Tom Cruise’s heavily populated neighborhood. I guess it could have coincidentally been the only one that was so placed, whereas others might have popped up in the Siberian tundra. Point being that the aliens couldn’t have predicted where humans would live thousands of years later.
This would be explained by the theory mentioned above that they weren’t pre-buried and the news-lady was wrong. But with that bit of exposition, it seems that the screenwriter intended us to buy the buried-spaceship story. And yeah, I vote that that explanation, while interesting, isn’t super plausible.
I’m pretty sure that Tim Robbin’s character mentions that they were buried for “millions of years”. But again, he wouldn’t know, no more than Dakota Fanning or the reporter. They’re all guessing.
And the machines are rising up in cities everywhere - in the same scene with the reporter she mentions NY, DC, and Chicago all going “dark” (or “down”, one or the other) - “when the tripods begin to move, communications go down”. I believe the first city to get hit is Moscow (but I could be confusing TWOTW with ID4 
).
Anyway, the things are rising up in populated areas all over the place which, to me, lends credence to the idea that they haven’t been passively “buried” for any length of time at all.
I assume they were rising up in unpopulated areas also. And it certainly makes sense that they’d be all over, just arrived or buried. Actually, neither the buried a long time ago or somehow constituted at the time theories make sense. ISTR that in one of the commentary tracks they mentioned that they wanted to be different. They were, just not logical.
Well, yes, they could. Places with the best geography for trade and husbandry; river mouths in temperate climates. Extra points for recognizing a nearby source of non-weather depended energy, such as forests or coal to burn.
And sticking to the virus plot device? The point of the movie was that technology is fallible.
[I did like the *Independence Day* play on that plot device.]