Tbf Replit is an online IDE for full stack development, that means that almost any idea you work on Saas dev tooling could be construed as a competitor.
Yes so you should keep that in mind if you sign documents specifically agreeing not to do this in the next 2 years... we may never know what the guy signed, but I assume interns at least sign NDAs.
The fact that CEO is a (insert bad word) is also true, however.