Mildly Infuriating

America has UNFUSED multi cords rated for 7A.

Indeed, we do. We have detachable appliance power cords built to be plugged into a 15/20A circuit, that connect to devices labeled to 7A, so the cord is similarly labeled. But, that cord is built with at least 18AWG wire, which is normally rated to carry 16A, not 7A. And it doesn't have our normal NEMA 5-15 socket on the downstream end, so it cannot be used as an "extension" cord.

There's literally nothing stopping you in America from plugging a 7amp rated extension cord, into a 20A outlet, plugging in two space heater on max and a third one on low, and pull 18-19 amps through a cord rated for 7, and no fuse or breaker is going to stop you from doing that.

Other than the fact that we don't actually have extension cords labeled (or rated) to carry 7A at all. Or that three 1500W space heaters will draw 37.5A @ 120V, which will easily trip our 15/20A breakers.

We could physically plug them into an extension cord labeled 10A, the lowest rating I've ever seen. But that cord will built with at least 16AWG wire, which is rated to carry 22A in chassis wiring. (It will also be very short.)

The key flaw in your argument is your failure to understand that the world does, indeed, protect its devices with household breakers. We do, indeed, build our devices to carry the full current that our household wiring could provide at an outlet, even where the device itself is intended to draw only a tiny fraction of that current. This is one of the most basic standards in use by UL, CSA, CE, and every other electrical certification body on the planet.

I know you understand the reason behind this standard. What I don't know is why you think the rest of the world doesn't understand it, and hasn't codified it.