Not really.
Newsom was re-elected in 2022 after COVID with 59% of the vote after getting 61% of the vote in 2018. You are completely biased here.
The real problem for Trump is that Newsom would give a sense of comfort to all of the independent voters who are looking for any way to reject Trump. He would absolutely crush Trump in debates. He is so well spoken and articulate. Trump would look like a buffoon next to him.
Forget the policies and blah blah blah crap about homeless people in San Francisco. Newsom would be such a contrast with Biden and against Trump that it could easily swing the election the other way. Style over substance.