People talking about others behind their back's might be part and parcel of everyday life, true, but an individual can choose to get involved, or not.
This is something I've learned, the older...and older...I get.
Sometimes you have to say something like 'the work wasn't done', but you don't have to talk about the people - others will learn soon enough who is reliable, trustworthy, etc, and who is a liability.
The truth almost always will out - and only sometimes is it necessary to go down the character assassination route. Sometimes silence can say a whole lot more.
(Having said that, my poor husband has sore ears, listening to my 5-minute moaning session, when I get in from work

)