If those were goalposts, they weren't clear. The miss is that the article in the link doesn't discuss VMs or virtualization at all, so talking about oversubscription/etc seemed like an ad-hoc commentary on the hardware configuration unless I totally missed that in the article, but searching for "virtual", "VM", "vCPU", "subscribe", etc didn't find anything. There's a limited amount of effort I'm gonna put into digging into additional links on "Planet Mainframe" pushing mainframes.
That aside, comments on articles are sometimes more general. "How do mainframes compare in 2021?" is a conversation which is not intrinsically linked to "should you oversubscribe VMs 66:1 for this specific workload?", and I interpreted your comment at the former. I wasn't talking about the article at all.