Yeah they should have upgraded to some restricted subset of C++ or new restrictive language ages ago. I mostly buy the arguments against having exceptions, perhaps even against polymorphism in general, but the argument against destructors, or atomics... hell no.
C has polymorphism. Inheritance-based virtual dispatch is just one kind of polymorphism. It's common to wire up polymorphism in C with bespoke data structures using tagged unions it function pointers. Changing an implementation at link time is even a form of polymorphism.
