Well, sometimes an end to a discussion is exactly whats needed. Sometimes. Like when theres literally nothing to do about something. Or the discussion is going in circles. Or when it would take shorter time to try it out in practice than have another meeting about the best way to implement it.
Doesn't "table the discussion" rather imply that they're going to come back to it at some point. I feel like "it is what it is" ends any further discussion on the topic.
i would argue that nothing is ever permanently tabled, merely indefinitely paused.
"had to cancel my vacation" doesn't mean they aren't vacationing, they might very well be staying home, and enjoying their time. They might not be doing that, but they might also be planning another vacation later, which i would argue is where it is no longer tabled, at that point.