You were probably already committed to it long before the meeting started.

Time for objections and concerns have already passed

There might be questions asked. And then you need the appropriate head of department to answer it. That's why they're there while not being expected to say anything.

I've had to implement systems I did not like. Systems I thought were inferior to other methods. But when the decision is made, it's made. And when asked how we plan to implement it, I answer with the plan and the steps. I don't undermine us by expressing disapproval in the formal meeting.

It's called professionalism.