I literally don't know how to say this any clearer:
Joe Biden is a WHITE IRISH DUDE. Harris's 2024 platform, was Biden's 2024 platform. Before he stepped down, Biden was polling WAY WORSE than Harris finished.
If your theory that it's all racism and sexism were true, we could expect A) Biden to have been outperforming Harris WITH THE SAME PLATFORM and B) Trump to have attracted millions of NEW voters looking to vote against the Black woman.
Neither happened. Trump 2024 was 75M vs 74M in 2020