It's long been a part of the press narrative about powerful Republican men. Oh, yes, they're a bit harsh, but the women in their lives might soften them just a bit. It's a weird mix of things. Bizarre assumptions about gender and gender dynamics (women are "nicer" and they have soft influence on their menfolk), implicit (but not explicit) acknowledgement that the men are, in fact, assholes (they are but you don't need to contrast them to imaginary versions of women in their lives to make that case), and, of course, a perpetual Lucy/football dynamic on the issues. Maybe this time Ivanka will make him do the right thing!
I have no idea if a Dictator Ivanka would be kindler and gentler than a Dictator Trump, but nobody else does either. There's certainly no reason to believe that a)she's better/nice/smarter and b)has or will use influence successfully.