It's worth being clear about how good this genuinely is: nothing outperforms petrolatum at sealing water into skin. It reduces water loss by over 90%. No $200 cream beats it on that measure.
Its real superpower is what it lacks. Almost every skincare reaction traces back to fragrance, preservatives, lanolin, or botanical extracts. Vaseline has none of them. That's why it's the fallback when a patient's skin is reacting to everything — there's nothing in it to react to.
This makes it the correct answer for eyelid dermatitis (where Neosporin and Aquaphor are themselves common allergens and frequently make things worse), for cracked hands, and for healing skin after a procedure.
One technique note: it has no water in it, so it doesn't hydrate on its own — it seals in water that's already there. Apply it to damp skin, or over a moisturizer. Used that way, it's remarkable.
A few dollars, available everywhere, unbeatable at its job.