Don’t get your suburban NJ housewife knockers in a twist, it’s just a figure of speech.
The problem is that suburban housewives—Floridian ones in this case—vote, and this kind of thing has the potential to turn off many of them, and others in the middle.
Whatever was in DeSantis’ heart and mind when he said it, it was a mistake. Fires up and hands an issue to the other side.
That would be “don’t get your knickers in a twist” not knockers. The American version is “don’t get your panties in a wad.” I suppose “don’t get your knockers in the wringer” would have been appropriate 70 years ago.