>Apple used to charge for all their software. I give FOSS credit for changing that.
I give the credit to Microsoft's market share. The fact is ~99% of Mac switchers like me previously owned Windows boxes and ran mostly proprietary Windows software. The free applications you get with a Mac are a way to cushion the blow of giving those up and in some cases offer features you just can't get direct equivalents for on Windows. Offering Time Machine, Photos, iMovie, Pages, etc for free has nothing to do with the existence of Libre software and everything to do with marketing the platform to switchers from Windows.
Clearly Libre software has had a huge effect on OSX, in fact the OS itself is based on free software and large swathes of its base components, tools and services are free software of one sort or another to this day. But none of those are name check features marketable to consumers other than just as MacOS.
In the dev tool arena yes, free software has had a huge effect. Specifically I think making very capable versions of VS available free was a response to the existence of high quality free .NET development tools. MS want people to develop on Windows using their own tool chains and if roughly equivalent free tools exist and become popular, there's really no cost to offering an equivalent for free any more given VS has to exist anyway.
> The fact is ~99% of Mac switchers like me previously owned Windows boxes and ran mostly proprietary Windows software
And now it's mostly proprietary macOS software. As you mention, the hard hitters in Apple's lineup are proprietary (Time Machine, Photos, iTunes, etc.) and the average user doesn't care that they can use BSD utilities on the command line. It's not dissimilar to the PS4, Switch etc. not being OSS consoles despite running a BSD kernel. Just because they use some FOSS parts for their OS, a FOSS ecosystem doesn't automatically appear.
I also think there's very little to no real community around Apple's FOSS, at least for their homegrown projects, not counting e.g. CUPS or KHTML/WebKit where they got the community for free when they took over or adopted the project. Note that even that didn't go without problems (e.g. with the KDE project) and Apple first had to learn how to behave as a good FOSS citizen.
Other community bits weren't as successful. OpenDarwin for example has shut down and PureDarwin needs a release still. Swift might be an exception and maybe we'll see more of that. I may also be very wrong here, I don't follow their projects too closely.
To even develop on macOS "officially", you need Xcode, thus an Apple ID, thus there is forced registration. You're transmitting your personal details to a US company and you agree to their terms and conditions, which can already be a problem. Are Iranian developers excluded? Cuban ones? Oh, it depends on the whims of the current US administration, you say? The GPL for example does not tolerate such limitations.
I don't know, but I think the atmosphere on macOS today is more like FOSS is present, but not really encouraged by the platform owner, and that's important. It's not like it was when macOS was still OS X and everyone was all "ooo, look, Ruby comes preinstalled!". Now that they managed to attract some critical mass of developers for macOS to be viable, they don't seem to care that much about FOSS anymore.
I give the credit to Microsoft's market share. The fact is ~99% of Mac switchers like me previously owned Windows boxes and ran mostly proprietary Windows software. The free applications you get with a Mac are a way to cushion the blow of giving those up and in some cases offer features you just can't get direct equivalents for on Windows. Offering Time Machine, Photos, iMovie, Pages, etc for free has nothing to do with the existence of Libre software and everything to do with marketing the platform to switchers from Windows.
Clearly Libre software has had a huge effect on OSX, in fact the OS itself is based on free software and large swathes of its base components, tools and services are free software of one sort or another to this day. But none of those are name check features marketable to consumers other than just as MacOS.
In the dev tool arena yes, free software has had a huge effect. Specifically I think making very capable versions of VS available free was a response to the existence of high quality free .NET development tools. MS want people to develop on Windows using their own tool chains and if roughly equivalent free tools exist and become popular, there's really no cost to offering an equivalent for free any more given VS has to exist anyway.