In it, he explains that while Grammarly's Terms of Service says they might store your emails, what they do looks different. They do a poor job of explaining it.
They do store what you (and only you) write but anonymized and only for the time it takes to optimize their engine. As soon as the model improves, it's destroyed.
Grammarly is the backbone of my writing. Grammarly has checked every blog post I publish. I am relieved that they care about privacy, and they don't sell our data. We got enough companies doing that already.
Every Twitter-thread should be a blog post. ↩