Do I need a bootloader?

I am setting up a hackintosh in an old Mac Pro tower. 4 hard drive bays means I can put each OS on a separate hard drive. I'm planning to run Windows 10, macOS High Sierra, and Mint. :)

I used to dual boot Yellow Dog Linux and macOS on an old Apple PowerBook, so I have some experience with GRUB. However, in reading up on setting up the Hackintosh I heard there were some issues with the current iteration of GRUB. And, don't even get me started on Basecamp. So once everything was installed I went with reFInd.

No problems with Mint or High Sierra, but Windows crapped out. I'm kinda new to this so a little grace is appreciated, but I did some research and learned Windows doesn't use an EFI-based bootloader. When I pull everything but the Windows hard drive out Windows fires right up.

My question is can I just ditch any bootloader and hold down the option key when I boot instead? I vaguely remember reading years ago that the bootloader also prevented the various OS's from messing with each other.

Thanks!