Which is more stable for playing and performance in general? I'm used to Windows, but have been considering a Apple computer with the good reviews I've heard of. Would the macOS version be as powerful or less than the Windows version of Dolphin?
You´d still have to use Windows anyway.
MacOS Dolphin doesn´t support Vulkan natively (the backend bases its workings on a wrapper) and GL is mostly garbage performance-wise due to outdated (and deprecated) Apple drivers.
Yeah, Dolphin runs noticeably better on Windows than macOS.
Looks like I'm sticking with Windows.