Simple things consist of a limited number of intuitively understandable elements. Easy things are, well, easy — they don’t require a lot of effort or education. There is plenty of crossover, but “simple” and “easy” are not the same.
For example, working retail at Walmart is simple. Almost anyone can do it, which is why it’s a low-paid job — there’s no supply constrain of potential employees to drive up the price. (Side note: price =/= value.) However, working retail at Walmart is a hard job. Being in contact with customers all day is emotionally exhausting, especially when you work for an exploitative company that doesn’t mind employee burnout.
It’s not the worst thing in the world when “simple” and “easy” are conflated, but it’s useful to remember why we have two different words and two different underlying ideas. There are plenty of simple tasks that are expensive because they’re difficult to execute.
I considered making this a longer post, but really, there’s no need. It’s a simple thought, after all ;)