I've known a lot of people who could build their deadlift through squatting. I've known very few who could build a squat through deadlifting. They are both important.
I relay this whenever I get a chance because I believe it's worth hearing (and repeating):
My grandfather died a slow death from emphysema. The last year or so of his life, getting out of a chair was a grueling met-con workout. I truly believe that a steady dose of squatting somewhere in his lifetime would have improved his quality (and quality) of life immensely. It's absolutely a keystone exercise. It doesn't have to be heavy, and it doesn't have to be with a barbell, but most people would be much better off having it on the docket.