Because there is a right well to tell fictional stories?
There isn't a single right way because there are infinite possible futures, and it's reasonable to assume that inventive SciFi authors would want to explore that huge space of possibilities. There are unlimited right ways.
Nor is there a single wrong way, but if all authors narrow their horizons to describing only simplistic futures in which most cultural elements remain unchanged then clearly there is a problem of deliberate myopia which will inevitably lead to a poverty of novel material.
It's a bit like surrounding oneself with yes-men --- it doesn't promote pushing the envelope and expanding the mind in new directions. In the context of SciFi, if cultural elements are shackled to present-day norms then it creates a literary monoculture with very few interesting elements. Even worse, it's factually incorrect, since we know that cultures change strongly with time.
It is acceptable to be factually incorrect in fiction, but when a whole genre that is predicated on gazing into the future knowingly avoids addressing cultural change then there is indeed a problem, and a very big one. SciFi readers deserve better than just present day stories adorned with spaceships.