You would have preferred Loretta Sanchez?
Feinstein and Brown supported Harris in 2016, but so did Elizabeth Warren and Cory Booker. There isn’t much of a separation between Harris and Leon on issues, and surely that – and not the age of the people who endorse you – is what matters.
As for Feinstein, I’m not crazy about her (or the triangulation school of politics in general), but let’s remember that when she took office hers was a traditionally Republican seat, that she was the first woman to serve as senator from California, and that and while the state has swung to the left she was one of people who set that pendulum in motion. Even today she’s probably not much if at all politically to the right of the state average.
Our government is currently dominated by actual monsters, I don’t see the point of postulating granfalloons like “old guard”.