Re: Expensive? We'll never know.
"no one actually says that Annapurna managed to meet the same performance requirements." - yes I posted similarly a bit after you. I don't know when it was said, but they bought Annapurna in ~jan 2015 for ~$350m. They may have realistically realised "so that's what arm yields, & we still wanna play with it, but we will buy our own test kitchen where we have full control". Annapurna may have other revenues/prospects, which would make the price chump change vs their intel cpu spend. If it adds intel leverage, it pays for itself on that alone.