For lots of East Asian researchers it's really embarrassing for them to send an email riddled with typos, so they spend a LOT of time making their emails nice.
I like that tools like this can lift their burden
OK -- I can see this. But I think Grammarly would be better than this.
But its suggestion system, where it spots wordy patterns and suggests clearer alternatives, was available long before LLMs were the new hotness, and is considerably more nuanced (and educational).
Grammarly would take apart the nonsense in that screenshot and suggest something much less "dark and stormy night".