When Hillary Clinton was the nominee, she was called "Hillary” by fans, opponents, and media alike. I was told “that's because 'Clinton' means 'Bill' in people's heads," and I didn't entirely agree, but OK.
Now Kamala Harris is the presumptive nominee, and she's "Kamala,” not "Harris.” There is no other President Harris.
Trump isn't "Donald," Biden isn't "Joe,” Obama wasn't "Barrack.” In 2016, it was possible that this wasn't gendered. But I can’t buy that anymore.