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    Your struct Class {Method methods[]; }; is the vtable, right? In C++ implementations, that only exists in classes that have any virtual member functions. "Standard layout" classes are guaranteed not to have any extra shenanigans like that, so the struct/class address is also the address of the first member. See also How do objects work in x86 at the assembly level? / In C++, is it valid to treat scalar members of a struct as if they comprised an array? and Commented Oct 3, 2022 at 6:01
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    Also, C++ has had "free" functions since the outset, inherited from C, and static member functions. You can take the address of a static or non-member function. But that's not OOP at all. It also has syntax for pointer-to-member-function (which require a this object to call it on); using std::invoke makes it easy to use those pointers on any object, mixing and member-function pointers and object pointers (of compatible types). isocpp.org/wiki/faq/pointers-to-members . But that was possible before C++11 (C++11 std::mem_fn and std::bind from <functional> make it easier.) Commented Oct 3, 2022 at 6:32
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    Anyway, C++ is not limited to Java's way of doing things, so it's weird to lump it in with them. You can pass around raw function pointers. Or if you want to do your polymorphism differently, you can roll your own, or for example use std::visit on std::variant objects by value, instead of needing references for polymorphism. Commented Oct 3, 2022 at 6:38
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    You're arguing that a C++ class isn't object in the OOP sense if it doesn't have virtual member functions? I'm not an expert on OOP theory, but you don't always need polymorphism for every type to be doing OOP, do you? So you can have objects, especially helper or sub-objects but not limited to that, where the static type uniquely determines the member function being called, not dispatch table needed. That's a special case of OOP where polymorphism isn't needed. Partly this is a nitpick; your overall point does work that this is C++'s traditional way to do OOP style polymorphism. Commented Oct 3, 2022 at 10:24
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    Function pointers are different from data pointers, yes, but having "functions as a primitive type" doesn't imply that they should be mutable. In fact having them as a separate thing from data references or integers makes them even more of a first-class citizen on par with those things, not a special case of another primitive type. As you say, C++ is designed to be ahead-of-time compiled, only executing machine-code that was generated before the program started running. Possibly from ROM. So it's compatible with pure Harvard machines. Commented Oct 3, 2022 at 10:31