In a perfect world, yes, we should all be empowered to be grown-ups and excuse ourselves from meetings that are useless. For run-of-the-mill useless meetings it's probably good general advice. There's often more to it than whether you have something to add to the meeting:

Sometimes the meeting has no clear agenda, and it's unknown whether you will be needed to contribute. Since you're peripherally involved with the project you're invited. The conversation may flow to some topic you need to weigh in on. These are bad meetings of course but they happen.

Sometimes you're simply expected to be present at a meeting even though you have nothing to contribute and there's nothing to take away that won't be in the e-mailed meeting notes. Your silent attendance is what's important, not whether you're engaged. In these cases, if you don't show up or heaven forbid, walk out mid-way, it will be noticed and you might face disciplinary action.

Sometimes you're working for a company where face time is important, so you'll have these meetings with the top brass and everyone tries to get an invitation, yet they just sit there doing work with their laptops open throughout. The goal is that the exec sees you and there's a chance he will know your face/name at some point. It's silly but welcome to corporate politics.