Almost the whole of black Friday is a nonsense. The only things worth buying are things you would have bought anyway but know are on discount.
Many items prices go up for a period before black Friday so they can then be discounted, and manufacturers even have cheaper versions of models of their products that they supply to discount chains and companies like Amazon for black Friday.
The only things I'd buy on sale are items I'm watching via camelcamelcamel which have hit discount, or software on discount. There are a few specific items I need to buy that I might buy if they're genuinely on discount but most of the stuff thrust in your face during the sales is cheap tat or lies.