How are you deciding if a test applies to your case? I can't do that from the subjective testing that he does. At best you have a comparison that Phone X is maybe stronger than Phone Y since there are no measurements taken to ensure consistency. For most people watching his videos all they are thinking is "Phone Y broke, therefore it is bad." which isn't fair.

Testing products properly is HARD. Companies have entire groups of people who that is their entire job and if they do it wrong it can costs millions in returned product. At the same time, if the test is too harsh, the customer is paying extra for a product that is over-designed for conditions the product will never experience.