Backward compatibility has been one of the main tasks, ever since the release of the first version of the plugin, and the developers behind it are trying to be committed to this aim. The second version, which will be merged into the core, is not going to provide full backward compatibility, but at least the plugin will continue to exist as a backward-compatibility layer that will allow any plugin that was developed in the plugin's first version with the ability to function properly.
It is obvious that developers are not going to be recreating the plugin from scratch and would rather be porting things over from the first version to the second one.
Thus, the routes will have to be prefixed, and the core will make use of a wp
prefix, and all of the custom routes will be assigned their prefixes. The wp-JSON
prefix that is currently used for routes is most likely not going to be used, and instead websites that will be using the plugin are going to get the old WP-JSON routes...