I'm ok with this analogy, but:
> But I don't see why getting started with a healthy diet has to be so complicated
This is a failure on your part. Dieting is an extremely hard and complicated thing for many, many people, as you can plainly see in this thread. That you don't see what's so complicated about your suggestion is a hint that you're missing a part of the picture.
Let's start with "Eat healthy": How do you do that? What do you define as healthy? How do you do it when you're strapped for cash? How do you even find healthy food, even if you know what to look for?
"Eat less": How do you determine what to cut? How much of it do you cut? Will cutting something cause you to crave something else?
"Burn calories": This is the hardest one. There's no easy way of checking how many calories you burn every day. "20 minutes of running" is very different from one person to the next, so even timing yourself isn't always enough. At the gym, machines sometimes have estimates for how much you're burning... but that's all they are, and it's a tiny tiny portion of how much you are burning.
"Don't over think it": I like what a poster said elsewhere in the comments: We need to start treating obesity as we treat mental illness. Just as "Just cheer up" is not an appropriate thing to tell someone clinically depressed, your suggestions are not useful to someone who is unable to lose weight. Do you think they haven't tried? What do you think is supposed to happen when people keep telling them "Just eat less" and it's not working, are they not supposed to overthink it?