JR has also invited Kamala, but many of us doubt that she will go. And in the unlikely event that she does go, all she's going to do is make a fool of herself once again. She is getting soft interviews from sympathetic media and she is not able to answer direct and clear questions.
25M views already of the full interview, and from there they get a bunch of clips that will circulate through social media as well. In terms of strategy it is clear that Trump is doing much better than Kamala.
Many people think that female candidates are no longer a big deal because the world is more equal but no, gender discrimination is still there and will always exist. I also believe that there will be many Democratic politicians or donors who will not be happy when their candidate is a woman. But simply because they don't have any better candidates to replace them.
Don't give me gender discrimination bullshit, if Kamala doesn't win in the end it's because she's useless, not because she's a woman. In a much more sexist world than now Thatcher won the UK elections, but she was not useless, she did not stay without knowing what to answer to simple questions and with a nervous laugh.