There's this certain comment I made more than seven days ago that I'm trying to delete but was unable to no matter how many times try despite getting no response and no upvote/downvote dust or whatever. Is this a bug thing or a feature?

Don't know without being able to check the comment.

Is this final and executory or will there be necessary witness consensus for this to get implemented globally?

All hardfork changes require witness consensus. Based on prior public discussions, I don't think these are controversial changes, so I think approval of these particular changes is likely.