Additionally, the above-linked JEP only proposes to make a small subset of types potentially null-safe. The goal there is performance, not correctness.
It will eventually be a goal. Java does things in steps. First will be introducing the syntax, then another JEP will take care of the standard library. Just like they introduced virtual threads and then introduced structured concurrency. Or like introducing records and then introducing pattern matching over records. Baby steps.
Additionally, the above-linked JEP only proposes to make a small subset of types potentially null-safe. The goal there is performance, not correctness.