It’s mostly an issue when you have them sharing boot drives via partitions. If you keep them isolated to their own separate drives, Windows doesn’t tend to muck with things. It’s because Windows is bad about killing bootloaders, and automatically setting itself as the default in the boot order. So if you have it sharing a drive, it’ll nuke your boot. But if you don’t have them sharing a drive, and boot via a loader on the Linux drive, there is no boot loader on the Windows drive to nuke.