They won't have access to your private project info (code, analytics, data etc.) if you don't host on their platform. NextJS itself is an open source framework.

They won't have access to your private project info (code, analytics, data etc.) if you don't host on their platform. NextJS itself is an open source framework. Suing for copying your product is tricky. In general I wouldn't rely on courts to protect your product IP. Execution is the only real moat. Any good product will have many copycats and competitors.