OS X's CoreAudio is still an incredibly well-designed technical architecture, designed by a team who really understood digital clocking from a hardware perspective and the importance of low-latency kernel support. It's still kind of amazing to me that it was essentially fully baked by 2002-2003. On Windows there's now WASAPI Event, which has a similar architecture, but for the longest time third-parties had to step in with a third party solution (ASIO) because the OS support wasn't there (and ASIO really only solves a subset of the problems CoreAudio solves). I'm frustrated by how little attention the driver and documentation side of things has gotten from Apple since then, but for some specialized requirements the underlying architecture is still just fantastic.
Audio people have been moving away from Apple over the past few years specifically because of show-stopping bugs introduced by new versions of the OS. This really never happens in Windows now and it's become more and more appealing to switch.
macOS has had a reliable low-latency audio API for years, when on Windows you had to resort to third party hacks like ASIO.
For years it has also had things like Audio Midi Setup, which lets you set up aggregate virtual audio interfaces from physical ones, dealing with latency compensation etc.
Or MIDI over Bluetooth. All of that out the box. It just feels it's been designed with pro audio in mind, compared to Windows.
Aside from the other replies you’ve already received that are spot on, macOS has also been consistently good at isolating the audio ports from coil noise / interference from the other electrical signals on both laptops and desktops. While “pro” audio folks are likely to be using an external audio interface anyway, having an audio jack that doesn’t garble the sound is one of many ways that Apple hardware engineers have been attentive to audio.
I wonder what MacOS has that Windows doesn't(which is a lot more backward compatible) that makes audio people stick with them.