I think what may have hurt (I'm aware we disagree on whether this hurt her campaign or not) is there was a gap where she did interviews, which allowed the media and Trump to paint her with the label of being afraid. Then when she did start doing more formal interviews, so much expectation was put onto them and Trump, with help from the press, was able to pick them apart and blunt any major positive comment (earlier today I saw that even 'entertainment' sites like Deadline were mentioning the edit in her interview on 60 Minutes).
Meanwhile, Trump can dance at a rally and get praise from the NYT, can cancel an interview in a place like Squawk Box that should have been a layup for him, and the usual suspects run cover with a tiny caveat:
I think Harris should have either done major interviews immediately or stuck to a plan of avoiding major media and doing smaller outlets (ditto for Walz, who has just been cocooned to the point where the main time I hear about him beyond all the "knucklehead" stuff is ugly smears from grifters/bigots and a hateful impression from Jim Gaffigan on SNL).
I saw a Politico interview with Bill Daley, who used to be Obama's chief of staff, saying it's Trump's race to lose, she is an underdog, she has to become better known because the campaign is so short. I assume given his ties to Obama a number of the people at the campaign feel this way and that's why this frantic push is happening after a lull, but I fear that the path taken may be the worst of both worlds and allows her moves to be spun as reactionary even if they are likely not.