I wouldn't call all the sugarcoating effective communication as I expect everyone in the company to understand that not wasting people's time will let them do more work and benefit the customer in the end.
Of course you would be. Why does it have to phrased in some extremely positive or negative way? Why not something like "I'm pretty busy working on x. If anything comes up in the meeting that needs my attention let me know afterwards and I'll arrange a time to chat."
A boss that conducts a useless meeting, knowing it's to hear themselves talk while knowing their subordinates are busy with important tasks that actually keep the company afloat is generally considered, and this is the technical term, a dick maneuver. His/her choice to have a time wasting meeting greatly increases the chances of those employees having to work overtime to accomplish a task on schedule, cutting into their family/personal time. Since most of these types of jobs are salary, there's no overtime pay. So yes, negativity is important in this matter. Why cuddle someone who wants to waste other people's time just to hear themselves speak and have some artificial self-important time?