Perhaps better to randomly select 10% of meetings, inform the participants it will be cancelled next week & that they should discuss whether it's necessary at this week's meeting, and then axe it. If they put it back on the calendar, let them. Then put out a poll asking if this was a useful exercise. Rinse and repeat until people start reporting it's not useful or you've cycled through all the meetings.

The reason I speculate this may be better is that it respects the agency of employees more, isn't such a shock to the system, and allows a buffer time to correct serious issues such as those mentioned in the top level comment.