the big difference is demna is mocking (or in his mind reflecting current times) with a stereotype even that ginger model body is not the same muscle type build that Tisci used.
also big difference is context Tisci actually finds his models hot and sees them as a celebration of male beauty archetype´s not as social commentary.
Demna ´s ginger gym bro model (Gavin is his name) represents the current gym bro /incel manosphere /internet culture archetype, he is pale and not classically handsome,
While in same show he has the looks maxing version of gym bro /incel manosphere /internet culture archetype thats has good jaw line and is classically handsome in the all white look.
These are all deliberate details of his archetype mockery fashion castings.
Demna partner husband is emo skinny so privaly its not even his taste or beauty standard to be with such an archetype.
Tisci models where more of the 90´s male supermodels healthy athletic but more emphasis on latin and racially mixed ideals and confronting it with high fashion design.
these men where Tisci ideal and he even try to look more like them by getting into the gym etc and constantly partying in brazil and ibiza with these types.
the beauty and ideals projected are not the same thing, same as hedi skinny model versus a pilates princes body ideal just because they are both skinny does not mean they mean or represent the same things or lives style´s ideals.
we are talking about fashion here

context matters , details matter allot.