If someone goes out of his or her way to tell you something is simple, it probably isn’t. And if you pay attention, I think you’ll find that the more elaborate the sentence containing the word “simple” is (It’s simple! It’s incredibly simple! It’s so simple a child could understand it!), the less likely “it” is to be simple.
If something is truly simple, there’s no need to mention its simplicity. It’s obvious to everyone. A button is simple: You push it. Nobody talks about it.
Here are some things that are not simple or obvious: How governments should budget their money. What, if anything, people should do to address the horrible things their ancestors did to their neighbors’ ancestors. When, if ever, it is acceptable to force any group of people to do anything they don’t want to do.
If you encounter a person who is convinced any of these things are simple, it’s probably because that person doesn’t cope well with complexity. Maybe you can help him. Be as patient as you can.