Maybe, or maybe I could assume that people who say he died because he didn’t try hard enough are assholes. I don’t take it personally, some people are just assholes.
But it doesn’t stop me from not liking the term, although my dislike has less to do with the loser connotation that that there is some value in fighting a battle with cancer. I happen to find the more admirable choice coming to peace with it than waging a war against it…
My statement was made based on my experience with losing a parent to suicide. When I’m describing the experience I don’t want it to devolve into someone telling me their opinion about mental illness. I’ve found telling people “he lost his battle with depression” to result in the least amount of unpleasantness for everyone.
Mostly I see this on tabloids at the grocery checkout lines, e.g. “Soandso’s Brave Fight For Life” where Soandso is some minor celeb whose name I only recognize because of the SDMB Death Pool. 
At any rate, it annoys me when I see it. (Fortunately, my mind’s likely moved on to other things by the time I’m paying for my groceries, so my annoyance is brief.) I guess those who don’t want to go through major radiation or chemo treatments for a few more months of life, are surrender monkeys or something. “Soandso’s Cowardly Surrender To Death”? That would be the logical converse. I’d love to see that tabloid cover.