;; Is it possible to do:

(define sob-default-comparator (make-parameter (make-default-comparator)))
    
(set-sharp-read-syntax! 'set
  (lambda (port)
    (let ((list-of-elems (read)))
      `(quote
         ,(list->set (sob-default-comparator) list-of-elems)))))

(parameterize ((sob-default-comparator (make-eq-comparator)))
  #!set((1 2) (1 2)))

;; What I expect
;;
;; => #!set((1 2) (1 2))

;; What I get
;;
;; => #!set((1 2))