Earlier quoted context omitted.
It's really not that intellectual or complicated. Just don't dress like a bum in public? Not everything needs a theorem or rigorous, tested, scientifically researched set of rules. Nobody is asking you to walk around in a 3 piece suit, there is no slippery slope or conspiracy theory here, it's just "dress like you give a shit about the public space and others in it".
But that’s a subjective criteria and one that’s obviously ripe for subversion. What about people’s right to freedom of expression?
The minimum effort is being clean enough that you don’t smell and don’t have visible skid marks on your clothes. Stinking up a cafe is antisocial.