In reply to JC.

Neil - they're a year into it. Frankly, if by now someone doesn't understand the importance of metaboxes and how they might be used, I question whether they should be leading this effort. I don't mean that they should know all possible uses, but they should understand enough that they aren't wondering if there are any that might not convert to blocks. Now, if they've surveyed the field and see that all kinds of metaboxes including those done with ACF, etc can be converted to blocks that's awesome. But then let's put that as a stake in the ground as a release criterion.

I'm fine with the idea that metaboxes would all become blocks - that makes a lot of sense. But it needs to be a fairly easy, robust process for those of us who've created these sites for clients.