An example that comes to mind is postfix (the SMTP daemon). It hasn't had zero memory safety issues, but nearly so. Certainly an abnormally low amount given the size/complexity of the project and the number of eyes on it.

It's also had a pretty 'normal' (read: higher) amount of non-memory related bugs such as SMTP smuggling of filesystem permission TOCTOU, so it's not like its devs are somehow really good at just not writing bugs.

Maybe they have chosen a software architecture that allows them to avoid complicated memory-related logic? I genuinely don't know, would love to hear from a postfix developer.

Outside of specially designed and verified code, probably not. Although there are certainly many projects where there are so few memory-safety issues that is is irrelevant in practice compared to other issues. Most of the issues I see are very easily preventable by using a string and a buffer abstractions that do bounds checking.

Also I think it is noteworthy that memory-safety issues are really well-defined and can automatically be found using sanitizers and fuzzers or verification tools. This is not the case for many other correctness issues and once memory safety issues are fixed this will remain as a major problem for all code.