To begin with, it takes rustup 3m30s to install on Windows. After rejigging the code again and again away from its naive implementation which works fine on Linux, to perform sympathetically towards NTFS, it takes the same rustup 14s to install. That's quite a performance gain! But it needed a lot of changes to rustup, and to Windows itself.
Yeah you can work around the filesystem perf problems on Windows to some extend. Unity builds are not just popular because it reduces duplicated compiler work but also because it reduces filesystem access. There is a reason why Windows games tend to pack their assets into archives.
Here's a talk on porting rustup to Windows: https://www.youtube.com/watch?v=qbKGw8MQ0i8
To begin with, it takes rustup 3m30s to install on Windows. After rejigging the code again and again away from its naive implementation which works fine on Linux, to perform sympathetically towards NTFS, it takes the same rustup 14s to install. That's quite a performance gain! But it needed a lot of changes to rustup, and to Windows itself.