Sorry if I came across as putting word's in your mouth samsara, but the OP had a positive outlook on his tinnitus, could be worse attitude, he is trying to cheer people up, he shouldn't be reminded that there are extreme cases of tinnitus where people would disagree. The majority of tinnitus sufferers recover their lives, I don't think striking fear into people because of extreme cases is necessary, we are all doing the best we can to cope with this condition, I believe having a positive attitude helps.
I personally know what severe tinnitus sounds like, surely all you have to do is go on to YouTube to find out, I would say mild is only hearing it in the quiet, moderate where you can here it with the TV on in the day, then severe where you hear it everywhere, even in loud environment s like you say, I even get to experience severe tinnitus when you get fleeting tinnitus for a few seconds. I think a lot of people know what severe tinnitus sound's like, that is why I believe people who claim to have habituated to severe tinnitus actually have severe tinnitus.
If you are OK with tinnitus now or getting better why would you trade tinnitus for lung cancer? My sister has a terminal lung disease, most people don't make it past their 20s, she is now in her 30s and she's has struggled the breath properly since birth, she is now getting worse to the point where she will soon need a lung transplant, even then her life will be cut short by half, I'm so proud of her for coping with such a horrible disease, I certainly wouldn't trade tinnitus with her illness, even if me tinnitus did get worse, I am grateful I am healthy.