I actually have the same tipe of thinning as his in the first picture and I can tell you
I have the same hair status as he does in the first pic and I would say that even with longer hair I would NEVER comb my hair like that because the shedding of combing in that way I would loose like 20-30 hairs every time, so that is a good sign that he does combin it that way because that means his hair is not falling
Combing your hair does not cause shredding. The hair that falls when combing would fall anyway. Its just ant hygienic and will make your hair look like further sh*t.