It doesn't really have anything much to do with a "dress code", though.
The jumping off point for the article is the length - or perceived lack thereof - of the Chancellor of the Exchequer's trousers. There was a particular picture which I don't seem to be able to turn up of him standing, in time honoured manner, outside Number 11, holding the red box aloft, which drew attention to his "high-water" trouser hems, but really, is that any more objectionable than the ungainly puddle of flimsy fabric around the shoes that most men nowadays favour?
All in all, I think Mr Osborne (quite possibly with the aid of one or more "stylists") is doing a fair job of making himself look presentable, without appearing overly narcissistic, or contrivedly populist. He's lost a fair amount of weight, and he's adopted a hairstyle that flatters his face and disguises his receding hairline, although, since Mr Osborne's hair is actually very fine and straight, I don't think that it's genuinely as "low-maintenance" as its short-and-neat appearance suggests.
I think that the real issue - vis-a-vis Mr Osborne's trousers, at least - is the state of garment construction, in general. We don't expect, or even want, our politicians to look like movie stars at a premiere, but Mr Osborne doesn't wear whatever he can find on the Final Reductions rail at Top Man or T K Maxx, he wears Timothy Everest bespoke. His suits really ought to look just, well, better than they do.
The article proceeds to criticize the current trend - and it's not a short trend, it's been around for at least a decade - of severely "undersizing" the modern business suit (I was going to say "lounge suit", but how many people nowadays buy and wear suits for no other reason than wanting to?) and ably illustrates the point with a photograph of Evan Davis. I've seen some very young urchins wearing those skinny-cut suits, and, on them, they can look quite good, but for fully grown men like Mr Davis, the "slim fit" look doesn't even look good on people, like Mr Davis, who are slim. The only way to pull it off is to put in enough time at the gym to develop big enough muscles that you can present a sort of "Incredible Hulk just about to bust out the seams" look.
And, leading on from the picture of Evan Davis, if men aren't going to wear ties any more, and assuming that nobody wants to adopt the full hairy sternum Saturday Night Fever look, shouldn't shirt collars be redesigned to look less, well, scruffy?