A divine arguments about the strategy to include API in core is in play- REST API meeting summary, Feb 4 had a blast with arguments.
We believe that the progressive enhancement approach is the best approach for continuing API development. Progressive enhancement is a paradigm the REST API project must adopt, if it’s an API we want to add to (without breaking backwards compatibility) over the next 10 years.
Ryan McCue, WordPress REST-API project lead, wrote Progressive Enhancement With the WordPress REST API.
Yes “Progressive enhancement” is important.
The only reason, I think, it should not be merged in WordPress core at this point is because it’s not *production ready* yet. WP-Admin parity may sounds overkill but the team still need to find their way (one or another) to ship in core when it’s production ready.
It’s great to see the arguments- and for sure it all would make it only better in the end.