I'm no engineer, but seems to me the length of the coupler puts additional stress on bolts. Seems to me that if the bolts were closer to the hitch then there would be less stress on them by a lever type action. I've towed heavier boats with trailer couplers similar to this but rated for 5000lb: https://www.zoro.com/fulton-trailer-...56/i/G3226027/ and you can see the couple is much shorter.

Of course the design with the break away and brake would have to be engineer differently.

I like the idea of Cobra having galvanized tongue but wonder why they did not use galvanized bolts.