According to Wikipedia, his dad is a media, entertainment and technology entrepreneur, with interests in film finance, viral video marketing, motion picture and television production and his mother is a model. I'm sure that helped.
To be honest, I don't like his designs most of the time, but I think he knows who he is as a designer, like I see a clear identity in his brand. I just think questionable taste and bad execution gets in his way a lot, though.
I think he benefited from a time in the last years where the gender-fluid and over the top approach got traction, specially in celebrities. I don't know how things will change in the future. Many places in Europe and America are getting more and more politically conservative when it comes to presentation (or more specifically, gender presentation) so sometimes I've wondered if designers like him will get affected somehow. Just some random thoughts.