Some polls suggest it would have changed the election. We will never know. However, it was so significant that there was a widespread coverup by Democrats, media, so called intelligence experts and others. Your question is better directed to your side. Remember the old saying "the coverup is worse than the crime." That certainly applies here.
I suspect that Biden supporters were most concerned about items on the laptop that could implicate Joe in Hunter's influence peddling schemes and simply just pictures of Hunter doing coke and prostitutes that would be embarrassing and potentially damaging to Joe.