This is my perspective. Why would anyone with any sort of political future go up against Trump, especially on short notice? 4 years isn't so long to wait if you're a rising political star or even a marginal one with aspirations. Just like I thought it was fucking stupid for Desantis to run on this go around, just sit it out, people liked him, and he was young. He could have gone into the next cycle as the heir apparent to the Trump coalition, instead he got pantsed in the primary by Trump and instead Vance is now poised to take the mantle in 2028. Hell, even going back to 2016 maybe people forgot that Trump destroyed Jeb Bush, Chris Christie, and Marco Rubio and Marco is just now recovering by spending 8 years devoted to getting back in his good graces while Christie took the alternate path of becoming a never-Trumper with the result that no one bothers to listen to him anymore.
That's a long way to say, I think it's obvious Harris has little political future, she's so artificial and unlikable that she's in HillDawg territory. She's from California so adds no value for the electoral map, and she was plucked out as a literal DEI choice for VP. Good for her, but all the easier to cast her aside once she gets trounced in November.