Manton and I do not agree on everything, but 95% of the time we get to the same conclusions differently. Sometimes he is facetious in his tone (you'd be a fool to take his faux imperiousness literally), but he is always worth listening carefully to. The forum was much more interesting and better dressed when his participation was appreciated.
You need to master the rules before you should try breaking them. Nearly every one of Mantons fits have been home runs, can we say the same about WAYWRN or this thread?
What we have a lot of instead on SF now are young, strongly aspirational* guys who are looking for the easy, quick way to the top, who are looking to take short cuts.
Instead of internalising rules, understanding them and then dressing accordingly, their locus of control is external - what's on sale, what I find in the thrift shop, what I see on tumblr, what's hot at Pitti, what's trending on #menswear, what fellow idiot-savants are hot under the collar about (e.g. navy cordovan boots).
Of course when you know nothing everything can look good to you. Instead of concluding that the rules don't really matter, consider instead that it's because you know nothing.
It's a sad state of affairs.
* - photos are often snapshots of a lifestyle, with the clothing being merely an accessory to the implied prestige of said lifestyle. Why post a photo of an outfit that tells me nothing about the fit, and with such poor colour balance that I can't tell anything about the colours either? Who gives a shit that you're drinking a glass of whiskey at a bar? Am I meant to be impressed by the fact that you're paying 6x the cost to drink outside? You're on f*cking SF, not WhiskeyForum.