> Sorry I hit the wrong button and sent an empty message.

No problem.

> That makes sense.  And I can imagine it is doable to write a generic
> wrapper in macro domain,
> which is agnostic to whether the passed procedure takes keyword
> arguments or not, but
> I don't know enough about Racket how to write it.

When writing a macro, it's easiest to have it output an ordinary
procedure call with the keywords spliced in:

`(foo ,a-value ,b-value #:c ,c-value #:d ,d-value)

This might potentially cause surprises:

`(foo ,@some-values)

if some-values contains keyword objects. I've never thought about how
they handle that.

keyword-apply also lets you give constant keywords in the call itself,
in addition to the variable list of keywords passed to keyword-apply.