If you analyse AAIB reports, ATSB reports, you name it - pretty much all pilots are incredibly reluctant to use the "M" word.
You mean they didn't just deprecate it 'cos it's French?
For better or for worse, but there is a culture of understatement among pilots. I remember reading some radiotelephony textbook for ATC, which said explicitly: if a pilot says "We have a little problem", you can be sure the problem is quite serious.