Characters in movies make mistakes and blunders all the time. Especially in horror films. It's really weird that for some reason people take so much exception to it in the Alien franchise. It's especially bizarre that when the same poster excuses bad science in a "hard sci fi" movies for the sake of plot advancement, but is unwilling to excuse flawed characters in a more fantasy-oriented sci-fi movie.
What's weird is that you're criticizing my opinion in the third person, by referring to me as "the same poster," when my post was literally immediately above yours.
Naturally, characters makes mistakes and blunders in movies all of the time. The point, which I think has been made pretty clear so far, is that 1) these characters are supposed to be some of the smartest, most experienced people around, and 2) their mistakes and blunders in the film are more egregious than we're used to in the franchise. In fact, we can probably add a third point, which is that the film is clearly trying to be more than just a "horror" film by introducing heaps of philosophy and literature to try to be a "deeper" experience than your run-of-the-mill sci-fi horror, which raises the bar on expectations for smartness.
Since we're comparing to The Martian, the Mark Watney character is very smart, but still makes a couple of disastrous mistakes that move the plot along. They're the kind of mistakes that even smart, educated people make, however, and you're liable to not catch that he made a mistake unless you're pretty smart and knowledgable, yourself. That's if the mistake is even shown, which I don't believe the ones in The Martian even are; Watney usually narrates what his mistake was after the fact.
Perhaps the best example would be The Thing. The plot of The Thing only happens because they bring the dog back to their base, despite the fact the Norwegians were actively trying to shoot it. The paranoia that the creature sets forth is used to drive each character's actions, resulting in their lack of trust and the failure to work together to solve the crisis.
If you happen to be suggesting that how the crew in The Thing reacts to the dog and how the colonists behave in Covenant are comparable, I couldn't disagree more. As Blackhawkswincup said, there's no reason to believe that there's something wrong with the dog. In fact, the film cleverly relies on our assumption that there's something off about the
Norwegians. It's not until later in the film that we realize that that assumption was wrong. We've all seen the film so many times that it may
now seem dumb to take the dog in, but it doesn't seem so dumb on first viewing, and even if you might've guessed that it would end up being a mistake because it's a horror film, the characters don't realize yet that they're in a horror film with extraterrestrial elements.
In contrast, we know that what the colonists do in Covenant is stupid before and while they're doing it. Go out on an alien world and sniff pollen without any environmental suits: stupid. Open a quarantine door that's keeping a deadly alien nicely contained: stupid. Shooting anywhere near your fuel tanks: stupid. You don't need to watch 30 more minutes of the film to realize how bad those decisions are, like you do with the dog in The Thing. You know that they're stupid immediately and it allows you to predict what's about to happen (ex. they're going to unknowingly bring an organism or pathogen back on board, the alien is going to escape because she opened the door and the colonists will be stranded because firing in the ship is liable to disable it), which helps to take the viewer out of the film.
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