From one (or more) of the comments here you can see that the reasoning for rust in topics about C is "everybody should write rust instead of C". At least for some people.

One other comment got it right, it is annoying to have multiple rust comments in every thread about C.

But you are right, best way to deal with these kinds of... i don't want to be rude, is ignoring.

PS Thank you for addressing the rest of the comment, not just the part you made personal.