Windows 11 is soon getting a new feature called Dev Drive, which uses an entirely different FS (ReFS) and reduced malware scanning, specifically designed for source code.
It's not "not scanning" completely, it has less aggressive scanning by default. You can turn it off fully if you want, but then, you can do that with folder based exclusions on NTFS folders too.
So, I'm not sure the perf increase can just be attributed to malware scanning. ReFS has some features that NTFS doesn't have like copy-on-write which might help in read-only I/O perf.
