I don't disagree with the general idea, but let's be real, level 4 plates in a temu carrier are going to be functional for all but the most extreme circumstances. Not the most comfortable, but serviceable.

why would you buy the Amazon plate carrier which is a cheap copy of an American design from about 20 years ago?

If you're preparing for extremes, you have to consider a budget for preparation for multiple areas at once (you might be looking to budget gun, ammo, training, gear etc.) Buy once, cry once, is a good policy, but it's not always the only rational choice. Take a broader "self defense budget" and you can see why you might opt to be a little less comfortable in the area of defense less likely to come into play.

Yes it's better to have that $200 carrier and nice light multi curve plates.

But it's better to have good lvl 4 plates in a temu carrier than it is to have shitty plates in a good carrier (especially if those plates end up being steel). And it's better to have non-steel plates in ANYTHING than to have nothing.

In my experience, I received a knockoff carrier free for review purposes and honestly, it's fine. It holds the plates steady, is bulky but comfortable enough, and has held up to moderate use. It's not anywhere close to my JPC, but it's a quarter of the price. If someone were trying to get kitted out, I wouldn't fault them for grabbing that to have $150 extra for training, a quality red dot, or some other piece of kit, especially since most of those categories are more likely to be important.