Of course representation matters. It matters in lots of ways and in lots of areas! But when you equate being progressive with happening to have a leader with minority characteristics you're making a mistake. Margaret Thatcher was the first woman prime minister. But she was a Tory and a bastard and her policies made peoples lives worse (including and especially minorities). Calling the Tory party of 1975-1990 progressive when they regressed the nation significantly would make no sense. The same is the case now.