It’s cured, slow-smoked (to an internal temp of 203 °F, much higher than what would be considered “well done” for steak), and then steamed. It’s literally the most cooked a piece of meat can possibly be without becoming inedible.

On top of that, it’s a cheap, tough cut of meat that only becomes delicious because of the complicated and laborious prep. When you buy a sandwich like that (which is pretty expensive), the extensive cooking process is most of what you’re paying for.