There are currently 37 questions which specifically mention backstab connectors, and given that there are over 400 answers using the word "backstab," there are probably many more questions which would qualify for this tag, but the askers didn't know the terminology.
As we're well aware, the common advice is not to use backstab connectors, but in looking through the answers there doesn't seem to be any canonical source for this. Given that backstab connections are (or at least were) UL certified, it would seem important to make a strong case against their use.
I propose we create backstab and include some canonical references in the tag wiki providing data about the risks of this connection type.