Actually, I understand armor quite well and have pretty extensive experience in real life with medieval armor (mostly Japanese).
Unless that chest and shoulder armor is reactive (like some real world tank armor, that actually has an explosive charge that blasts outward to counteract the incoming force of a shell or missle), then no, his shoulder wouldn’t just be scraped up. It would be decimated. Whatever hit the armor in that picture penetrated it and destroyed it. It is millimeters from his flesh. Do you really think that huge amount of force was dispersed in those remaining millimeters leaving his flesh (which is FAR softer and more fragile than that armor) unscathed?
If I cut clean through your samurai do (pronounced like “dough”, the Japanese chest/belly armor) then guess what. I’m cutting clean through you. If my blade got through the armor layers then the next thing it touches is your gut and its going right through that like a hot knife through butter.
The point of armor is to stop or dissipate the injurious force BEFORE it comes in contact with you. If it fails, then you ARE getting injured. If it fails as spectacularly as in that picture, then you’re getting hurt BADLY.
It is precisely my real world experience and first hand knowledge that makes me find those kinds of pictures so silly.