Wow. That's definitely not okay in my books. I'd be upset, too!

I edit very little myself. I tidy up incorrect punctuation etc. or might add an obviously missing little word (typo), or make those kinds of minor additions if English is not the person's first language and what they said isn't clear.

But mostly, I will ask the writer to clarify or make changes such as the one someone made on your story.

I'd have deleted it, too!!

Thanks for sharing this.