I never know where I sit on stuff like this. On the one hand if you’re confluent I think it makes total sense to own this part of your infrastructure. Especially if it lets you improve your operability story.
On the other hand I feel like projects should try and use open source “building-blocks”, like etcd and zookeeper, when building their distributed systems. Not only does this help iron out correctness bugs, but it also means that more people are familiar with the quirks, limitations, requirements etc.... of these tools. For example, I think I would be frustrated to hear that K8s were implementing their own raft.
For example, there's a great Raft library for Go [1] that any project can use to implement distributed consensus without a separate running program. I find this to be a better approach with the same collective development and community testing advantages but without requiring more operational overhead.