They got privileged early access to an unreleased frontier model to harden their systems, with Anthropic engineer support, and likely were able to use it to make other product optimizations tangential to security too. A blog article afterwards is a cheap price for unlocking that access, regardless of how well it paid off.
Not how I took it, but that this was a lot more marketing than content, while their other, older blogposts are more content than marketing. It is of course all content marketing, for Cloudflare. That doesn't mean it has to be bad (anemic on meaningful content). On the contrary, it being good is kind of the whole point.