Commoditizing software was never a strategy, at least until a very recent stage. Open source software projects commoditized software either by being vastly more successful and out-competing their alternatives (gcc[1]), or by being a singularly better value proposition than their alternatives (linux[2]). The companies which have "commoditized their complements", used "open source as a growth strategy", or "become entrenched monopolies" have always had a rather sketchy relationship with open source software, which is why they have preferred to avoid an actual free software license.[3]
[1] Back in the good ol' days, everybody made C/C++ compilers. OS vendors made compilers highly tuned for their hardware and software; others, like embedded vendors, made compilers tightly integrated with their tooling. Then gcc showed up everywhere, and started producing optimized code better than the tuned products. By the time LLVM appeared (2003?), its only real competition was gcc and a fork of gcc.
[2] Originally, Unix vendors had incremental improvements over their competitors in specific areas (IBM: SMIT/JFS, SiliG: graphics, etc.). Initially, Linux was a joke. Then it became as stable as the vendor OSs and the hardware it ran on was cheaper. Then it ran on any hardware. It may never have achieved feature-advantages over the competition, but taken as an entire package, the competition couldn't provide anywhere near enough value.
[3] IBM's a funny case, especially with Red Hat. IBM hasn't had a functioning software (or hardware?) product for at least 30 years.
You’re just describing the process of how all that software became commoditized. Software the everybody needs to use is simply a commodity now, and that’s why the more generically useful something is, the more open source support it’s going to have. Companies (usually) don’t want to build their own infrastructure, the want to spend their money investing in their value adds, because that’s where they get their RoI. A company could build their own web server, operating system, compiler, database... But their customer are unlikely to see any benefit from that, which is why they find themselves with an incentive to improve open source software. That’s the reason big open source projects attract large corporate sponsorship, not to satiate the ideological motives of “top talent”.
[1] Back in the good ol' days, everybody made C/C++ compilers. OS vendors made compilers highly tuned for their hardware and software; others, like embedded vendors, made compilers tightly integrated with their tooling. Then gcc showed up everywhere, and started producing optimized code better than the tuned products. By the time LLVM appeared (2003?), its only real competition was gcc and a fork of gcc.
[2] Originally, Unix vendors had incremental improvements over their competitors in specific areas (IBM: SMIT/JFS, SiliG: graphics, etc.). Initially, Linux was a joke. Then it became as stable as the vendor OSs and the hardware it ran on was cheaper. Then it ran on any hardware. It may never have achieved feature-advantages over the competition, but taken as an entire package, the competition couldn't provide anywhere near enough value.
[3] IBM's a funny case, especially with Red Hat. IBM hasn't had a functioning software (or hardware?) product for at least 30 years.