Look, I think I've demonstrated I'm not a fan and not really qualified to do deep commentary, but I had enough schadenfreude to follow up on this when it blew up and from what I gathered, it's really not as bad as you're making out. Apparently the joke was about a bunch of Bow's siblings having names that rhymed with his, one of them being 'Sow' and a farmer, and looking like a stereotypical American farmer. This seems to have been judged offensive, but there was no direct or explicit association of 'slavery' or 'plantation.'
Does it matter? She doesn't have any respect for She-Ra as an IP except to insert her shallow original characters and abusive last minute romance. She jumped to a position she never merited in the first place, did a terrible job at what she what hired to do, got pitches by actually competent non-white animators unfairly blacklisted, so it's only fair that she gets attacked by her own fans for something completely unrelated to the actual damage she caused.
Normally I would be a fan of something like She-Ra. I like 80's cartoons, I liked the He-Man 2002 reboot. But reports of the direction the creators of She-Ra have taken lead me to believe that I would not like the show. I have a limited amount of free time to spend watching kid's cartoons, and so I pass until/unless I should hear some things about the show that make it seem more appealing to me.
The only people it appeals to are vapid shippers who have no problem with romanticizing abusive relationships and don't care if the world building, characterization, plotting, etc is sloppy and inconsistent.
It doesn't even respect the original show. All the character designs were redone from the grown up, unnecessary original characters were crowbarred in, the cast and crew constantly mocked the original show without any self-awareness...
Mattel doesn't want anything to do with NuRa. The sheer incompetence behind it got other show pitches like
Astur's Rebellion unfairly blacklisted for featuring non-white main casts.