It's the people on the ends of the Bell curve that make it seem futile. They make the news and cause overreactions. When a large number of people are involved (17,000 per season on Whitney), the number of "outliers" gets significant.
Risk information is for the majority of people who care and are able to grasp it. If they seek that information, it's waiting for them. The permit Rangers should be providing basic info to those who didn't do their homework, with handouts for details.
I'm not a fan of long signs warning of everything. Better to have short simple warnings and a way to get more info. The most effective sign I ever saw was hand written at a dangerous beach on the Na Pali trail in Kauai. It was a list of the people who died, when, and where they were from.
There's no reaching people who think they know it all or those who can barely tie shoelaces. Common sense is not all that common.