There may be a few Frankenstein apprentices who fit into this category, but I'd go with the simplest answer: it's (relatively) easy money with few strings attached.
Troons are trampling one another to throw tens of thousands of dollars at any surgeon willing to do an amhole installation. They willingly ignore known deleterious side effects and outcomes by calling them TERF propaganda, and gladly sign away their rights to complain about or sue if anything goes wrong, on what is essentially experimental radical surgery. As long as they come in with a penis/vagina and walk away with a stinkditch/rotdog, they're as happy as can be.
Sure, afterwards, they'll have to deal with scarring, dilating, fistulas, sepsis, pseudococks falling off, pseudovaginas shutting closed or being too shallow to do anything but clean up, chronic pain, and a litany of other problems, but the surgeons won't care, because they'll be too busy picking the color of their new Mercedes, or vacationing far away from any noisy eunuchs.