Their IDEs can show them the graph you're talking about in a much richer form, lets them navigate through it, check what each commit did, who did it, and even change the graph (as everything in Git is changeable) by removing/rephrasing commits for example. I don't see how using the terminal actually helps anyone understand git, quite the opposite.
Git Tower is actually a great tool, but I believe Gits core concepts cannot be understood well without lots of experiments with the bare Git CLI (what helped me most was making toy repos → testing my hypotheses on how things work → observing/inspecting results).