Yes and no. I myself am quite thin, so anything that does not have, as you say, a 'slim' look will appear to be baggy on me. So, for me, and many people like me, 'slim-fit' clothes are simply clothes that fit, as opposed to clothes that look like a tent.
However, I agree that there is a trend of wearing clothes that are slim beyond fitting well. I am not one to endorse men wearing skin-hugging jeans and t-shirts that look like they were made for pre-adolescent girls. But I would be equally appalled by someone with a slim physique wearing a shirt that, when tucked in, droops down his legs because of the amount of excess fabric on it.
Everything should be exercised in moderation. Italian tailoring has always been slimmer than English tailoring, but it still fits well. It complements the physique. You seem to be associating the term slim-fit with the aforementioned skin-tight jean-clad youths, which is a gross generalisation.
Originally Posted by intent
The key word is fit, not slim/skinny.
The word 'fit' doesn't actually describe anything. It simply implies that a piece of clothing fits its wearer. But people have different physiques, which is why companies adopt the terms 'slim-fit', 'petite' (for women), and 'big and tall'.