My sister‘s Standardbred likes his low-port kimberwick. He didn’t like any jointed mouthpieces she tried. I don’t know if that is just him, or a standardbred thing.
Typically horses who need space for their tongue are not happy in any 2 or 3 piece snaffle, they need some kind of port for tongue relief. Usually that’s big, fat tongue horses and ponies, but it could just be the individual 's need.
My warmblood mare is like this. Putting her in a low port mullen was life changing.
There’s a reason why the neue schule Conrad Weymouth (big square port at a 45 degree angle) is called the “warmblood”! It’s a lot more common with them than you might think, although I think it’s only been in the past couple of years that people have figured out that ports are friendlier to some horses than snaffles are.