I think the goal with this message is to kick off a deeper, more meaningful engagement between engineering and the various communities that use MediaWiki. But it's hard to see how the message will move the needle. It's jargony, as if aimed at an audience of software developers. The mechanisms proposed for engagement are technical - report bugs in Phabricator (hardly anyone receiving this message will know what that is), nominate release blockers (which are what?), or join IRC meetings.
The message contains nothing about vetting the features themselves, no outreach from the engineering team to the receiving communities, no translation from English or facilitation for community members who don't read and write in English, etc. So I think it's fair to ask that Engineering work a little harder to reach the people who have objected to previous feature rollouts where they live. The reactions from these people have presumably driven the desire to engage more fully, so the nature of that engagement must actually reach them. If these things are actually being done, that's great and I think readers of Wikimedia-l would love to hear about it.