It's not as dire as you suggest. To simplify a bit, you can take the set of ~75% predictions created by a model (which can be an actual model, or it can be just

It's not as dire as you suggest. To simplify a bit, you can take the set of ~75% predictions created by a model (which can be an actual model, or it can be just the meta model of whatever model Nate Silver wants us to trust right now), and then see what percentage of them were right. If that comes to 75%, then the model is well-calibrated, and it's a solid enough basis to assign a 75% probability to future 75% predictions, which is often as good as you can get when trying to make decisions and plans.