The 'retirement' makes little sense technically either, for the reason that you mentioned, but again that would be likely a case of doing it more for the emotional impact of it being their collective story ending.
I suppose it would have been less impactful to have them say the crew was being decomissioned but not the ship.
At the time fans could have maybe rationalised (given there's so much that kinda is open to rationalisations) that just the crew was being stood down, and the ship would have been re-crewed and sent out with a new command crew but then Generations blew that out the water by having a totally new ship! Never mind though.
Regarding the corridors, again, none of this stuff makes a lot of sense if you stop and think about it - a Connie has in TFF identical corridors to the 'state of the art' Galaxy 90 years later, but then in the next film they are different, along with the bridge - so, yeah, each director just did a ship revamp to suit themselves.
As it turns out, Abrams did the same thing!
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courtesy of Saquist