alt Hacker NewsNo, that is completely wrong. It is exactly because the questions are not identical that the system works. That is what allows for multiple versions of a popular, important question to catch attention from search engines, and send everyone to the same, correct place.
Perhaps your objection is that, because the target question is not literally identical (for example, maybe a code sample has different variable names, or the setup has an irrelevant difference in the container type used for a collection, etc.) that the answers don't literally answer the new version of the question. That is completely missing the point. It's not a forum. The Q&A format is just the way that information is being presented. Fixing the issue in your, personal code is not, and never has been, the goal.
You are positing that only questions with cosmetic or extraneous differences are marked as duplicates.
That's not the case. As a maintainer of a popular project who has engaged with thousands of Qs on SO related to that project, I've seen many Qs marked as duplicate where the actual answer would be different in a non-trivial manner. When I look at who all moderated on those Qs, they are usually users who haven't contributed to that topic at SO.