A trailer that can respond and assist a hard brake

we already have that, and it's legally required for trailers above a specific weight in many places

I presume the concept is "you have need to tow a 5,000 pound trailer and you just have your Toyota Corolla"

To provide effective towing, your vehicle has to be rugged, powerful, and weigh enough to not get yanked around by your load, meaning even when not towing it's a heavy vehicle. Instead this imagines a self-driving, passengerless truck that plays follow the leader and hopes it's close enough to towing to be allowed.

Of course, the problem as illustrated is that they show a tiny little thing towing a big payload. The physics just doesn't work (I suppose if the trailer is hollow aluminum and the tow is lead...)

If I had to guess. Its because "hitches are ugly."

Why did we skip past cool tech and go straight to idiocy.

We didn't skip past cool tech. We plucked a bunch of low hanging fruit. And now that fruit is gone. So we're getting weird with it to justify further consumer spending.