I think this is probably one of the better scenarios for Trump.
The voters who supported Trump in the last election don't care about identity politics. They want jobs, jobs, jobs, and money to put food on the table, not a lecture.
Where does Gillibrand improve over Hillary? Hillary already maxed out in the suburbs, I don't see Gillibrand even getting the urban turnout Hillary got, and I certainly don't see her doing any better in rural areas. Maybe you fix your Detroit turnout issue and flip Michigan back, but I struggle to see much more than that.
Whether you like Trump or not, there's not a whole lot he's done that's surprised anyone, so I doubt he's going to push away a huge amount of the voters who supported him in 2016. Dems need to do something to win those voters back or increase turnout among their base (especially given the abysmal levels of black turnout in 2016). Kirsten Gillibrand checks neither of those boxes.
If you want a woman, Michelle Obama is seriously a much better option.
Also, don't take for granted that she's got no scandals. Hillary's scandals were already known before the election because the RNC has been going through her family's history with a fine-toothed comb for the past 30 years. You couldn't say that about many other Democrats at this point in an election cycle, and Gillibrand is no exception.
Then again, Trump's approvals are pretty awful, so maybe things shake out differently. All I'm saying is I think Democrats have better options.
These types of things were said about Trump. Look at how bigoted he is they said? He'll have to do worse than Romney with minorities, and they'll come in droves against him, they said.
He was friends with The Clintons, they said. He's a plant! they said.
Look what happened.
Or how 'bout Obama in '08, his record was more conservative than Hillary's, but he perfectly imagined himself as otherwise in the last year.
Oh, and y'know what other "conservative"-"moderate"-"liberal" made it big? Oh, Lyndon Johnson.