So "Stop" signs should say "Stop because there might be another car coming from another direction and you'll be able to avoid it if you stop and see it coming".
I'm not sure that type of explanatory thing would work with most signs. Instead, we need:
1) people we trust to determine what the signs should say so that we are willing to listen to the signs.
2) Easy access to more details explanations of why/what the sign means.
3) An easy method of questioning the sign makers and and getting them changed or removed when they when either the sign maker was wrong or it's simply no longer needed.
Information is pretty easily available, especially as it pertains to things like the "don't feed the animals" sign in the GGP post, and it's not unreasonable to expect people to seek out an explanation (e.g. park staff) rather than just ignore the rule. The problem often comes down to people-- at all stations of society-- believing they shouldn't have to follow certain rules all of the time. People know that going 20mph/30kmh over the speed limit is more dangerous for themselves and others, but lots of people still do it. On more complex topics, explanation are available. But most people want simple answers, and complex issues don't have them. So when they disagree with something but don't have the full explanation to understand and determine things for themselves, they will listen a person who gives easy answers. And they'll tend to listen to whichever person gives an easy answer they already agree with. 99% of political rhetoric is about giving easy answers to complex problems, most of which would have been solved long ago if there was an obvious easy answer instead of countless details and edge cases and other factors to consider.
I don't know how you solve this problem. Human nature means most people don't spend a ton of time trying to understand all aspects of a problem that may only vaguely impact them personally. I don't expect anyone but a very small minority will study geopolitical history & current circumstance enough to have a well-informed opinion on something like whether the US should stay in, or withdraw, from a missile treaty. There's countless other examples of that sort too.
involved in the decision-make process
I'm not sure how you get around the lawmakers problem. Everyone can't weigh in individually on decisions made in a massively complex society. Being involved in the decision-making process means voting for people to handle those things. Are there other models of citizen involvement that better limit the impact of corrupt/biases/stupid lawmakers?
I'm not sure that type of explanatory thing would work with most signs. Instead, we need:
1) people we trust to determine what the signs should say so that we are willing to listen to the signs.
2) Easy access to more details explanations of why/what the sign means.
3) An easy method of questioning the sign makers and and getting them changed or removed when they when either the sign maker was wrong or it's simply no longer needed.
#1 is probably the hardest.