Java streams don’t infest your project. They also don’t throw away the error system of the language. They are also leagues more maintainable than a reactive project.

Ignoring the maintenance issues, reactive applications do not yield better performance on realistic I/O-bound workloads: https://julien.ponge.org/blog/publication-performance-and-co...

So all you end up with is less maintainable code and more developer headache.