The grandparent post is incorrect. H/w silicon validation or constrained random testing hasn't been the norm for 10 years, it's at least 20, which us when I first got into that industry.

And yes, we had coverage driven verification back in 2005 as well. No, we didn't "tape out" our CPUs until we'd hit our testing plan which was defined by coverage metrics.

P.s. pre-si verification had testing pipelines way back then before they became the norm in s/w.