There may be a grain of truth in all that, but the kindest, most pleasant and well-mannered people I've ever met have not necessarily been the best dressed. Many of the most arrogant, vacuous and unscrupulous have been well-dressed. I don't really see the connection.
I'm sure this fairly universal point will have been made by many others.

However, I do suspect your theory is being presented only half-seriously...

There is no objective state of being well-dressed, but aye, people ought to dress the best they can in their own contexts of culture, age, and physical hawtness. If the weather is warm and the person is young and fit, this means wearing curve-highlighting and fashionable clothes with some clean colours and sharp lines in there, with lots of skin exposed.

If they are a right minger (whatever age) they should cover all that shit up and maybe dress more conservatively, go earth tones like a nice brown paper sack over the head, nicely pressed, etc., style over fashion. And of course work on their personality.

i guess the main moral point is to be charitable & compassionate for other ppl's eyes.

Although I recognize the value of dressing well (versus dressing like a slob), I can never subscribe to the "respect for others" arguments posited elsewhere on the men's clothing internet message boards, er fora. It seems too much like "respect" arguments used by mafia hoods and rapper gangsters (and cops); in other words, with an unsavoury element of threat.

I agree with the Cap'n that there is a moral dimension to dressing well.  Indeed, the virtue gained from it is my only route to that particular commodity.  The clothes do rather offset my many undesirable qualities.