Ours was long strided, very smooth ride, walk, trot, canter or gallop. Easily ridden for hours without you getting sore. She did the Michigan Shore-to-Shore Trail ride several times with her previous owner, camped out on the picket line. No flaky TB attitude to match the stereotype you hear about. A real lady all the way.
You have to look at the basic structure of the animal, some designs just do not add up to the most comfortable ride under saddle. How the legs are proportioned, neck, parts hung off the skeleton, angle of shoulder and hindquarters all contribute to gait comfort for the rider.
Sometimes it is the rider, lots of folks are scared to let a TB move naturally, always trying to keep them small moving. Horse argues, so rider puts more gimmick tack on to help hold them back when horse insists. Rider is just not used to covering that much ground each stride, walking or any of the TBs other gaits.
We see the same thing with our Sporthorse types, just walk away from other breeds who don't have such a big stride. Ours are half TB. I don't hold mine back to match other short-moving horses, it just makes them irritable so a fight easily develops. Some animals just can't walk together no matter how hard the rider's try. Same with many of the Gaited horses, they move BIG when gaiting, other breeds can't keep up. I personally have a hard time trying to walk with short strided people, have to take baby steps.
Get on the TB, see how he feels. Several rides are recommended, especially if your current breed moves very differently. You might need some adjustment time, to find out if horse is suitable to make you comfortable with his gaits.