I am not a native speaker of English but I think I heard years ago that there is a slight difference. Clothes is more appropriate when you want to focus on a piece of what you are wearing (e.g. a suit, a pair of trousers). Clothing, on the other hand, is an expression that is kind of a generic term of all things you can wear.
However, I also think that in common conversations “clothing” and “clothes” can considered to be interchangeable.
But as I just said, I cannot provide any proof of my opinion.