Mfg. published tow ratings are magical marketing numbers. You will run out of 'payload' capacity long before ever reaching that magical tow rating.
Payload is what is available after weight of truck (all passengers, all cargo, hitch weight, everything in/on truck) is subtracted from trucks GVWR, while paying attention to weight on rear axle and tires vs their ratings.
MFG. 'Fine Print' (often not seen/read or ignored)
*Maximum trailer weights in pounds for properly equipped vehicles with no cargo
*May vary depending on model, trim and/or powertrain.
*Maximum Loaded Trailer Weight assumes a towing vehicle with any mandatory options, no cargo, tongue load of 10-15 (conventional trailer) or king pin weight of 15-25 (fifth-wheel trailer), and driver only (150 pounds).
*Weight of additional options, passengers, cargo and hitch must be deducted from this weight
So YES that GVWR trailer at 7500# is more than the Durango's 7200# rating and the Sequoia's 7400#