Errors are always relevant. Just as you can drive a car with the Check Engine light on, you shouldn’t be able to turn the light off just because you can still drive it (and you should be going to a mechanic very soon!).
So even if the error is known but irreconcilable by us, it’s better to be aware there is something going on. And trust me, we make adjustments (well @cgrunenberg does 
) to our sync engine with every release, including ones trying to improve anything we can regarding CloudKit.
And now, it’s 3:13 AM… 