>>215133096
IIRC the original film is set in 2122. This isn't confirmed in-film (I don't think) but it's probably established in the novelization/screenplay or other secondary stuff. Then the events of Aliens occur 57 years later, and the fan consensus seems to be that it takes place in 2179 specifically (maybe that's mentioned in the screenplay, maybe not). So late 22nd century.
>>215133873
Yes and no, and there's tension between these two attitudes among the characters. The two contradicting attitudes are alternated to make the drama work. During the initial wake-up sequence, the dominant idea is to show that they're all cocky and some of them don't take her too seriously. But Ripley does assert herself and their CO does tell them to read her file. She gets their attention, and during their initial exploration, everything they see lines up with what she's been telling them. When they get into the building they do take the op seriously because it's obvious that the shit has gone down.
At the critical moment, when they move into the hive, Gorman blinks and gets locked-in, rather than calling everyone back to reset. That's the critical fuck-up, and it's written so that it's perfectly obvious to the audience so they can say to themselves "what the hell are you doing". Then the major problems begin. Gorman even had a smug look when they found the PDTs: "Heh, we found 'em, this'll be easy." He must have thought that they were all "hiding out" over there, or something.
But yes, overall the "strict" culture shown alternates with obvious fuck-ups like leaving the hatch open. Ripley even creates her own problem when she mashes elevator buttons, allowing the queen to follow them in a second elevator (she can hardly be faulted for this panic-error, given the situation, but still).
