Java 10 will receive updates till 2025 still, so nothing to worry about - it´s just like with Windows, they release a new version with new features, but the old ones still get bug fixes and security updates for years.
According to my measurements, it is on par with Zulu Java performance-wise. But any user can replace it with his own Java version if he wants.
We will upgrade to Java 11 in the future, but it is not a pressing issue.