It's true that there are extensions to x86, but 99,99% of software out there (the one you'd commonly install on Windows or find in Linux distribution repos) doesn't use those instructions or maybe just detects the features and then uses it.
I don't recall encountering a "Intel-locked" or "AMD-locked" application in more than 20 years of using x86. Ok, maybe ICC, but that one kind of makes sense :-)
I don't recall encountering a "Intel-locked" or "AMD-locked" application in more than 20 years of using x86. Ok, maybe ICC, but that one kind of makes sense :-)