Barely anyone actually believes that that an amulet protects them. But it might make them feel better when they wear one, it's their lives. Why is this Muslim going out of his way to dictate how people dress and also destroy an amulet in the process. This is real stupidity.
Are you Muslim? If you are not then I suppose it's not very relatable to you as a non-muslim. As Muslims we hold the principle of "Enjoy the good, and forbid the evil",. and this is something that's obligatory in our faith upon every Muslim according to their abilities, and knowledge. A lot of Muslims actually believe that amulets can protect them against evilness, or diseases. Thats why you will find a lot of Muslims on different social media warning against it, and telling people that it goes against the rulings of Islam. Most are based on sincere advice from person to person, I don't think it has something about dictating. We Muslims do not have the right to force or dictate what others do but we can at least explain why its wrong with goodness, and sincerity.