I did not read this as gatekeeping, rather I read it as an opinion on the suitability of C for kinds of project. If vim + make isn't enough, then C is probably not the appropriate language. Not that you shouldn't use C if you don't use vim + make.

We always talk about how good engineers "choose the right tool for the job". I don't think expressing an opinion on what the right kind of job is for a particular tool should be out of bounds. (Setting aside whether the opinion is correct or not.)