Similarly, Linux kernel developers have added support for asymmetric instruction availability in their schedulers through features like “CPU microcode updates”, which allow the OS to query a processor’s available instructions sets at runtime and make more informed decisions about thread placement as a result.
This is bullshit, the microcode is not in any way a mechanism to query any information. It's an opaque blob provided by Intel and the system firmware. What's happening with Alder Lake is that AVX-512 is disabled through microcode, but if you're not Intel or a motherboard manufacturer, there is nothing you can do about that.
If your goal is to make AVX-512 usable on your computer, don't bother with it. It will not magically make things go faster.
Patents have been an issue for Linux before. For example, memory deduplication (KSM) was delayed and modified to avoid a patent on using hashes for this purpose, resulting in a potentially inferior implementation due to patents.