The announcement that Jakarta EE cannot use the javax.* namespace is great news and provides Jakarta EE with a clean slate on which to build and innovate the future of Enterprise Java.
The Original Proposal
It had been envisioned that the javax.* and jakarta.* namespaces would coexist after Java EE 8 and, as it evolved, the jakarta.* namespace would be used for new features of exiting APIs and the innovation of new APIs. This would have ensured backward compatibility from the start. And overtime the use of jarkata.* would eclipse the old namespace, but never actually replacing javax.* namespace. So, forever more Enterprise Java developers would have to explain why there are two namespaces. A constent reminder of Enterprise Java’s past (something we are trying to move on from).