France's fast breeders have been failures, and they recently cancelled their next iteration trying to make them work. China doesn't have any fast breeders beyond research work, as far as I know.

It may be that sodium cooled fast breeders had a fundamental materials flaw that was not recognized soon enough.

https://link.springer.com/article/10.1007/s11665-010-9763-5

Thanks for that. Even if those jurisdictions are not using fast breeder technology, I think they're still pretty good evidence that nuclear proliferation is low risk.