Except that we're really running AMD's x64 ISA, not Intel's, so this moat concept doesn't really fit with the reality. Intel clearly thought x86s days were over when they started their 64 bit Itanium effort, and then quickly (and luckily) managed to get back into having a competitive x64 implementation when they realised they had backed the looser. I'm actually quite impressed with how they pivoted as lesser companies would have had trouble ditching that sort of investment.