I think there are good points you make that people should hear, but less people will listen if you turn them away by making grotesque comparisons.
I'm going to be pedantic with this: calling something "a cancer" is not comparing it to cancer. The phrase "X is a cancer" is bombastic and inflammatory, which is intentional. It's neither a simile nor grotesque, at least in my dialect of English.
As for the actual point: I see no reason to venerate C. Nobody should labor under the false pretense that we, as an industry, are brilliant enough to reliably write safe, cross-platform C. We haven't managed to do it for the last 50 years and, given the current state of static analysis on C, I don't have any particular hope for the next 50. I'm going to keep on writing it, but I don't intend to venerate it or convey that expectation on anyone else.
This absolutely hits the nail on the head. This is masterfully put.
The problem with a great many successful things in the world is there's a very human tendency to "saint" them and attribute a sort of mystical infallibility/ineffability to them. As though they weren't just "fit for the purpose and in the right place at the right time", but rather "a work of genius - the right solution for all time, now and forever." (C.f "end-of-history-fallacy").
That's how technology stagnates - if we, as a community, can't admit something's got room for improvement, it simply won't.