As a commercial OS, OS X/macOS was quite compatible: FOSS Darwin core, FreeBSD userland, POSIX compiant certified UNIX, built-in Python and Java support. Apple

As a commercial OS, OS X/macOS was quite compatible: FOSS Darwin core, FreeBSD userland, POSIX compiant certified UNIX, built-in Python and Java support. Apple/OS X also contributed some nice things, by way of funding, hiring main devs, and/or heavily supporting certain FOSS projects: LLVM and Clang, CUPS printer drivers, WebDAV, WebKit, libc++, and Swift. Also designed some widely used interface standards: FireWire (started by Apple), Thunderbolt (co-designed with Intel driven by Apple) which eventually turned into USB 4, Mini DisplayPort (later incorporated to the official DisplayPort standard, and even the design re-used for Thunderbolt). There was nothing to "maximize rents" as there were no rents for the most part of OS X's journey until later Cook. They put out good products and people bought them, getting them out of near certain bankruptcy.