OK, I watched the whole thing.
Clearly whether or not anyone would find any of this relevant depends on what they intend to use their knife for. If it is just opening Amazon boxes, cutting string, tape, apples and pears etc it likely is not relevent or of any concern.
However, many people do carry folding knives for potentially far more demanding and critical tasks. First responders, military, SAR etc come to mind. Folk that go hiking, camping, hunting, fishing, climbing as well as professionals that venture to remote areas - geologists, biologists etc. In addition to a utility knife I usually also carry a dedicated knife for "any emergency". That includes, yes, self defense. An emergency could be cutting the seatbelt to free someone in a vehicle. Or an attacking dog.
This guy tests a Spyderco Manix 2 Salt which fails under what is really a moderate blow. This is a knife marketed to appeal to yachters and fishermen. Two groups where there is real potential for some serious use - and stresses. The former may need to cut a sheet, halyard or mooring line in an emergency, maybe in a raging sea. In what is already an emergency a collapsing blade during a fall or other blow could now be compounded with a severed or partially severed finger or two. Any good size ocean fish can be very strong and difficult to control when landed and they don't have to be the size of a large tuna or marlin. Again the potential for being subjected to a sudden unexpected blow in use is there,
I consistently maintain that a fixed blade knife is the knife of choice for any and all these categories of use. However, the fact is most people prefer the relative compactness of a folder clipped into a pocket, in a belt pouch or other attachment. Most people are sensitive to the idea of carrying a substantial fixed blade belt knife. In some work places knives of any kind are not permitted (Oh yeah I have been there), and a clandestine pocket carry is the only option. I usually carry a good sized emergency fixed blade and a utility folder, but sometimes the emergency blade is a folder. Depends on where I am going and what I am wearing. So yes, to many people how strong the lock is on their knife is important. This guy only tests a few knives and the purpose is obviously not a guide to strong and weak knives, rather just to suggest people take this into consideration when buying a folding knife if they are shopping for more than just a very light duty cutting tool for use in controlled environments.