Why the no-fork and not a branch? Just maintain a dev branch on SQLite, the same as on, say, NGINX, and only merge into mainline after > 3 years of use by the

Why the no-fork and not a branch? Just maintain a dev branch on SQLite, the same as on, say, NGINX, and only merge into mainline after > 3 years of use by the lots of users that are safe using dev. Will get it battle tested better and fatser, and in the hands of far more users. Why have a not-a-fork fork?