Submitting your original, important, unpublished, research to some random entity. I would be VERY surprised if more than 2% of academics think this is a good idea.
I wish my own manuscripts would be that important...
Regarding security concerns: there is an open-source version for those who want full control. The free cloud version is mainly for convenience and faster iteration. We don’t store manuscript files longer than necessary to generate feedback (https://www.rigorous.company/privacy), and we have no intention of using manuscripts for anything beyond testing the AI reviewer.
I guess the paper would be complete enough to publish as a preprint at the stage where this specific service is most useful
Good point; where I used to work we didn't really do preprints though. And PIs were all incredibly paranoid, making any uploads to third parties a real no-go