If you buy premium coffee and prepare it in a gentle, controlled way, salt in it is likely to make the experience worse. For everyone? A pinch may be fine.
One of our favorite coffee gurus (and maybe yours), James Hoffman, digs the science of this in the video below.
He examines how a pinch of salt can tolerate the rough edges of a less than perfect cup of coffee and balance the taste. Why does it work? Because a good cup has the right kind of bitterness (and not the kind brewed in an unwashed truck stop urn).
Interesting science lesson aside, the videos are worth a watch to see poor Hoffman making his way through cups of salted instant coffee.