I find that Best Buy is good for prepackaged stuff: like a full laptop or a full desktop. In fact, Best Buy prices are competitive if you're buying those kinds of items.
Best Buy sometimes has GPUs or SSDs at good prices, but its less common. I still price-compare at Best Buy because of that small chance that they win in the price wars, but my #1 goto is still Microcenter (or Newegg if from online).
The fact of the matter is: Amazon's cables have such low-quality assurance on them, that they're untrustworthy now.
I think for cables specifically, Monoprice has created a good reputation and a good price. Unlike Amazon, who hides behind "marketplace sellers" and "comingling", Monoprice puts their own reputation on the line when they sell cables.
Ultimately, if Amazon wants to be a "marketplace seller", they can. But Amazon needs to do a much better job combating fake-sellers, low-quality products. I'm not even anti-Chinese or whatever, I'm fine buying cheap Chinese stuff as long as there's some long-standing brand name that is willing to take the reputation hit if things go wrong. (Ex: why I'm fine buying cheap Chinese goods from Walmart, but not fine with buying cheap Chinese goods from Amazon. Walmart does step in and take responsibility)
Otherwise, its just Alibaba Russian roulette with your stuff. Maybe things work, maybe things don't, maybe things will blow up your laptop. Maybe the 18650 cell will blow up in your vaping device and give 3rd degree burns on your face. Or the 18650 cells will create a garage fire burning down your new scooter. Etc. etc.
The problem is the distinct lack of brands and accountability on Amazon. If a Monoprice or Best Buy cable destroyed laptops or caused fires, we'd all blame Monoprice or Best Buy. But if an Amazon item does the same, we somehow don't blame Amazon, but some indistinct unnamed entity.
I bought a Samsung Galaxy tablet from Best Buy's secondary (opened packaging or complete returns) inventory that has been absolutely flawless. I was never a tablet person ("if it doesn't fit in my pocket, I want a damn keyboard") but I've ended up using it every damn day.
Best Buy sometimes has GPUs or SSDs at good prices, but its less common. I still price-compare at Best Buy because of that small chance that they win in the price wars, but my #1 goto is still Microcenter (or Newegg if from online).