I'll disagree with the parent and use the following definitions: Science fiction is a genre that explores the social consequences of technological advancement

I'll disagree with the parent and use the following definitions: Science fiction is a genre that explores the social consequences of technological advancement on humanity. Science fantasy is a genre where futuristic technology just serves as a backdrop. Star Trek at least somewhat delves into the social implications of technological advancement (although less than many other works of sci-fi). The reason that people get bogged down into discussions of "hard" and "soft" sci-fi here is because hard sci-fi, being more grounded in reality, might have more predictive power in its social commentary.