Every project and programmer shouldn't feel they have to justify their choice not to use Rust (or Zig), who seem to be strangely and disproportionately pushed on Hacker News and specific other social media platforms. This includes the pressure, though a bit less in recent years, to use OOP.

If they are getting good results with C and without OOP, and people like the product, then those from outside the project shouldn't really have any say on it. It's their project.