Boil the macaroni in salted water for 8 to 10 minutes until just past al dente, then drain, rinse under cold water, and spread on a baking sheet to dry for 5 minutes.

Whisk together the mayonnaise, white vinegar, sugar, mustard, salt, and black pepper in a large bowl for about 1 minute until smooth and the sugar has dissolved.

Add the cooled macaroni, carrot, celery, red onion, and green bell pepper to the bowl and fold gently with a spatula until everything is evenly coated.

Cover with plastic wrap pressed to the surface and refrigerate for at least 2 hours, then stir, taste for salt, transfer to a serving bowl, smooth the top, and dust with paprika before serving.