Thoughts on the final part:
First:
"Fire is an energy source that gives life to things and allows many others to function." I literally cannot think of any reason to include such a statement unless it's to foreshadow what's coming next:
Rebirth from the flames. Given life, being allowed to function.
But basically what I've concluded is...still even the doctor doesn't know how Dabi survived. Dabi wouldn't answer him when the doc asked, which means there IS an answer. And it was specifically mentioned that Dabi shouldn't have lasted as long as he did. So there is a reason he survived.
Second:
He's saying the same shit that AFO says about Shigaraki.
"Only good for destroying and killing."
So just like Shigaraki is set up to prove AFO wrong, Dabi is set up to prove that his flames aren't only meant for death. Not only through whatever rebirth or regen thing is about to happen, but also that he can do good with his flames.
