Because, while he doesn't have the fatal flaw (to dems) of being a Jew, like Shapiro he is still a very white, very privileged, male. (I'm not even talking about his incompetence as governor, that doesn't seem to matter to the Dem base).
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Who is the likely Dem DEI candidate? Michelle keeps saying she's not interested, but she checks off all the boxes: Black,female, radical, belligerent, hates America, Obama.

Michelle Obama is the very living definition of the phrase "Never meet your heroes". She's likely the most entitled person on the planet in addition to being extremely tone deaf. I also doubt she'd be up for the effort it takes to actually participate in a political campaign.

Newsom is the far-and-away front runner for them because he'll pull in more than enough money for the campaign. You're very much right in that he has to pick a woman to run with him or the AWFLs stay home. So who are the leading women in the dem party?

There's the Big Gretch Whitmer in Michigan. There are a number of posters here who live in Michigan. To a man and woman they know she's been a lousy governor but won't ever admit it out loud because they just can't be seen criticizing their own side. So she's a meh choice.

Amy Klobuchar of Minne-haha. She's so unlikeable the producers of the show "Veep" tailored parts of the character Selena Meyer after her.

Kamala Harris has managed to convince herself that the democrat party writ large didn't position her for success. She's in for another go!

AOC is dumb enough to think she'd have a shot.

Fauxcohontas Warren wants to be President. But in addition to being a fraud, and a communist...she's also massively unlikeable.

And...that's it. Their depth is horrifically thin. Won't stop this board from glazing whatever intellectual nobody they vomit up to be their nominee for '28, though.