This question already has an answer here:
Utopias and dystopias are a genre loosely connected to Science Fiction and Fantasy. They often are set in the future, occasionally involve technology which has not yet been invented, and otherwise wear the trappings of sci-fi. However, they normally focus heavily on social and political commentary, and the involvement of obvious sci-fi elements is often peripheral. Sometimes it is not present at all.
Consider, as an example, this question:
In its current form, the entire body of the question is as follows:
I've searched for this short story for years.
In it, everybody is given $1,000,000 at birth. A single guy figures out how to game the system. Everybody thinks he's crazy to buck the system but he wins.
(In case it's not entirely clear, this is a story-identification question.)
There is no mention of any sci-fi elements, but this clearly looks like a dystopian story of some kind (a planned society with some unusual or different social rule). The answer might have sci-fi elements, but it's a long-established rule that answers do not make questions on-topic, so we can ignore that as irrelevant.
Are all utopias and dystopias on-topic, even if they do not have any "classical" sci-fi or fantasy elements like magic or futuristic technology?
Utopias and dystopias are not adequately addressed by How much dystopia is needed to be on-topic? because it does not have an answer. They also is not adequately addressed by Are works that aren't SF per se, but have occasional SFnal elements on-topic? (e.g. spy movies), because it has nothing to do with utopias and dystopias in particular, and applying it to utopias and dystopias across the board is likely to be controversial. The question I used as an example above was repeatedly closed and reopened, and we are likely to see similar disputes across the site if this discussion is swept under the rug as a duplicate of an old, unanswered question.