Hi. This is my comment you keep linking to. Your understanding of what happened is flawed. I do not have signs that Linode was rooted in that compromise. The signals I do have is that they had their database compromised, and likely secret key material. That allowed attackers to crack the hashes offline, and then authenticate using MFA.
IMO, it's plain wrong to categorize that one as "getting full root control plane", where it was instead the compromising of individual accounts that may have had no access to the resources on an account.
https://news.ycombinator.com/item?id=10845985
Doesn't it seem kind of crazy that folks get full root control plane on linode so frequently?