The first one actually makes sense in a moral and logical context. (Eg. It's technically correct that a bullet can make you quit smoking, but it still isn't right.)
I'm not sure about the others, but the last guy (from Oregairu iirc) was definitely pretentious. Like being vague about his ideas just to appear smart and productive. The hand gestures was the best part.
Looked up the top-right one, the original phrase is
人は殺さられば、死ぬ。
Which, indeed, means "If a person is killed, they die".
I listened to the whole scene and it sounds like the character does have something weird going on with his body, which prevents him from dying, and what they are meaning to say is "normal people die if they are killed, but I don't".