The only bad thing about a good quality wet food is price. Wet food does not rot teeth, it makes no sense that a wet food would stick more than a chewed up dry food.
Low quality wet have the same problems as low quality dries, bad coat, stinky poo etc.
wet food generally has less carbs which is great for an overweight dog, cutting out fat is usually not a good idea even though that's how diet foods often do it, it's much better to cut carbs, wet food does that.
For cats wet food is a must because dry food has SO many carbs (25%-50% carbs) where as a wet food is usually under 10% (3% is what I've seen in what I buy) and it causes all sorts of problems from kidney disease to urinary blocks and especially diabetes. cats are carnivorous, they cannot handle carbs well at all. Dogs are omnivorous so dry does not hurt them, they CAN handle the carbs but wet is just as good. It is just wicked expensive.