could you please clarify what you see as the ban? I think i've missed it.
i can't see they've banned anyone, just imposed age restrictions which already exist for other fashion weeks.
the doc cert, well, it's like providing proof you're fit to work. most people have had to do it, or pass a physical to qualify for work at one time or another.
I don't see anything wrong with any of this. if you're too young, you can't work (just like the normal labour market) and if you're sick/unwell you can't work.