Conor Heun is a 10th Planet OG. He changed my perspective on toughness, teaching me that it was largely mental. He had his jaw split in two from the first punch in one of his fights and went on to win a decision, even though his jaw clicked every time he was punched in the face. That's mental toughness.
It is pretty common for MMA fighters to say that they will not tap to a choke. I think Conor may have overstated his position here - I like to think he would tap rather than have his neck twisted out of shape, but his larger point was that he was making a calculated decision when he decided not to tap to a deeply set armbar. Notice that his examples are being knocked out or choked out - the ref can stop the fight in those cases to prevent further damage.
As Conor reports, his arm was really just sprained. He felt that was an acceptable amount of damage. If it had been a truly career ending injury that he was dealing with, I don't think he would have reacted the same way.
Conor realized he could survive and felt there was a certain amount of damage that was acceptable.