If you want logs to go into ElasticSearch, k8s does that today - you just write to stdout / stderr and it works. I don't love the way multi-line logs are not combined (the stack trace problem), but it works fine, and that's more an ElasticSearch/fluentd issue really. You'll likely want to replace the default ES configuration with either one backed by a PersistentVolume or an AWS ES cluster.
Could it be more efficient and more flexible? Very much so! Maybe in the future you'll be able to log to journald, or more probably be able to log to local files. I can't see a world in which you _won't_ be able to log to stdout/stderr. Maybe those streams are redirected to a local file in the "logs" area, but it should still just work.
If anything I'd say this issue has suffered from being too general, though some very specific plans are coming out of it. If writing to stdout/stderr and having it go to ElasticSearch via fluentd doesn't meet your requirements today, then you should open a more specific issue I think - it'll likely help the "big picture" issue along!
From what you wrote, it seems that lots of people consider logging in k8s to be a solved issue. I'm wondering why is there a detailed spec for all the journald stuff, etc.
From my perspective - it will be amazing if k8s can manage and aggregate logs on the host machine. It's also a way of reducing complexity to get started. People starting with 1-2 node setups start with local logs before tackling the complexity of fluent, etc
Is that the reason for this bug?