Every major system API I can remember working with that didn't hide const behind a typedef (like Win32's LPCSTR and whatnot) has it const first.

Speaking of Microsoft, though the API's hide const with a typedef, the MSDN samples are predominantly "const char" order.

I've never seen a man page with "int const".

Searching all of the man pages I have installed on an Ubuntu 18 system here (literally grepping through all of /usr/share/man), I found just one with "char const" or "int const". Namely this one:

  $ man guestfs-hacking

        int
        commandvf (char **stdoutput, char **stderror, unsigned flags,
                   char const *const *argv)

        int
        commandrf (char **stdoutput, char **stderror, unsigned flags,
                   const char *name, ...)

Though these can be reordered, it's clear they were intended to follow English.

In a compiler implementation, it's troublesome to enforce the order compared to processing a simple list and setting/checking flags in some data structure, diagnosing invalid duplicates or mutually exclusive situations.

I was speaking of declarators, not declaration specifiers. In C, a pointer type is part of the declarator and not the specifiers. Therefore, the CV qualifier is also part of the declarator except for the one exception of the specifier. Regardless of whether specifiers were intended to follow English (and this claim is dubious), declarators certainly were not, since it's often more natural to read them right to left, and it's generally most natural to read the left most type-specifier last.

example: char *x[10]; Translated to english this is naturally stated as an array of 10 pointers to char. Not char something something array.

Edit: later on I see you've moved the goal posts about the "uselessness" of cv qualifiers on pointers. I don't know what to tell you, I think that's bullshit, and there are a number of viable use-cases for them regardless of whether you have encountered them. I'm just addressing the consistency part here.

There is no choice about where to put const inside a declarator; the position affects the nesting level which alters the semantics. So there is no debate to be had there.

Note that in declarators, the const is necessarily to the left of the thing it qualifies, so why would we put it to the right of int:

   int ** const ptr;
                ^^^ this is what is const

   int * const *ptr;
               ^^^^ this is what is const

   const int **ptr;
         ^^^ ^^^^^ these two are const

   extern const int **ptr;
                ^^^ ^^^^^^  const and const
   ^^^^^^ unrelated to const

Your third example could just as easily and correctly be:

  int const **ptr;
            ^^^^^ this is what is const

Const qualifies the object. Whether the const is applying to the "int" in some way or is an independent type specifier that applies to each declarator is pretty philosophical. I say it's the latter. The fact is, the very allowance of a cv qualifier in the specifier list introduces an inconsistency or imbalance.

Ultimately this is one of the ultimate bikeshedding argument. There's no right answer, and appeals to spoken language aren't particularly compelling when bikeshedding C of all languages. This isn't AppleScript.

I'm not even terribly interested in this particular point. I'm more interested in quashing the notions that bikeshedded opinions of language syntax have some divine providence. It's just bullshit.

Also, declarations can have multiple declarators.

   int const *p, volatile **q[3];  // syntax error! not how it works

No "int const", no i[array] instead of array[i], no deceptive trompe d'oeil nonsense like:

   int* p, q;

When we write code, stuff that looks weird should signal a bug. When bug-free code looks weird, that is a distracting false positive that grabs my attention for no reason. Don't add gratuitous weird.

Eh? int is a noun, surely? How does int describe an int?

I can imagine cost and long being adjectives for the noun int.

Further, C is not like English and even if it were, one could not conclude that it should be or should continue to be. Moreover, that it was designed by English speakers is not evidence that it is like English or should be like English: most assembly languages were also desiged by English speakers.