Is there such a thing as "function attribute correctness"?

Question

Ok so C23 adds function attributes to the language but I'm not sure if anyone actually considered how they are supposed to be used. Consider this example:

[[deprecated]] int foo () { return 0; }
[[nodiscard]]  int bar () { return 0; }

int main()
{
  typedef int foo_t ();
  foo_t* fp1;
  foo_t* fp2;
  foo_t* fp3;

  fp1 = foo;
  fp2 = fp1;
  fp3 = bar;
  fp1();
  fp2();
  fp3();
}

Some things of note here:

• It is not possible for me to specify an attribute in the typedef because apparently attributes are not attached to the type.
• The only warning I get in gcc or clang for this entire program is during fp1 = foo; assignment. foo is deprecated.
• I do not get a warning when assigning fp1 to fp2.
• I do not get a warning when calling a deprecated function through fp1 or fp2.
• I do not get a warning when calling fp3 but ignore/discard the result.

Furthermore, there appears to be no check between function declarations and definitions. This compiles cleanly:

[[unsequenced]] int foo ();
[[nodiscard]]   int foo ();
[[deprecated]]  int foo () { return 0; }

Why would I ever want a compiler to allow such nonsense?

Function attributes are not attached to the type, so how can we get "function attribute correctness" and making them work as intended? Or are they just plain underspecified/broken, added to the language at a whim, to be fixed at a later point when someone can be bothered to actually examine the consequences of them?

Am I missing something here?