That's not what the article is advocating at all. A table bend is basically a deadlift. It's all about keeping the back straight so the heavy lifting is done by the hips and legs.

"Lift with your legs" is advice to avoid hurting yourself when you are lifting something for the sake of actually moving it. It's not an exercise plan.

When exercising, you want to lift with your back specifically to strengthen the muscles involved. The lift they're describing is basically a deadlift, which is one of the key lifts involved a typical weightlifting plan (lifting with your legs in another one, so don't skip that).

You do have to be careful not to try to lift too much weight to avoid injuring yourself, but as long as you don't overdo it, you will reduce your risk of back injury because your muscles will be stronger and less easily injured.