It's an operating system kernel that can apparently provoke a response from a number of people in spite of having two buzzwords prefacing it.

Presumably something like CoreOS which makes extensive use of containers and any security feature it can get its hands on.

If I personally put my own opinion on it, I don't like unnecessary use of containers because the model gives you a lot of outdated dependencies, and I'm not sure whether containing a vulnerability once it happens is that noteworthy.

Old skool "use good, secure code. update dependencies" and not focusing on containing a vulnerability produces a much safer system IMO.

The cloud part makes much more sense when combining it with the user land. I think that's also where OpenBSD (or *BSD in general) really shines, everything is very coherent. Regarding Linux, I'd probably see CentOS/RHEL as "modern hardened cloud OS" with all it's measures in place. But even as a complete BSD beginner, I find OpenBSD or FreeBSD easier to configure than CentOS, which IIRC requires a lot of manual whitelisting of capabilities for server daemons.