The problem is that by doing this, Democrats will be alienating their base, focusing on a demographic that isn't a factor in their equation, and that's why, although people are saying they should just run a stereotypical White man in '28, that idea could be problematic.
Right now, the mainstays of the Dems are Black people, women, young people, gays, and minorities in general, as these groups are the future of the party. I've said it in another thread that the Democrats are adamant on having either a Black person, a woman, a person of color, etc as their leader.
White people don't really have a place in the Democratic party in terms of the future, that's not to say their support isn't necessary, but they're not the prime focus, which is why a lot of them have turned Red in recent elections. Appealing to the needs of White voters is more of a Republican thing at this point and time.
It's pretty evident through some of their presidential candidates the past 2 of the 3 elections, that's why even tho Biden won, many Congressional Dems were not exactly thrilled simply because they didn't believe in terms of image and representation, Biden wasn't sustainable in maintaining the voting base's support.
There's a reason why when Kamala took over for Biden, the whole party, specifically the voters, were ecstatic because she's the type of representation that best describes this base, and despite her woes, she has a very good chance of potentially winning the primary in 2028 because of the aforementioned.