That invented falsehoods “shouldn’t be on Wikipedia” is not much consolation when in practice academics, journalists, and others regularly copy false claims from Wikipedia without independently fact checking them or citing where they got them. Nor does it ultimately much matter whether false or distorted claims were deliberate or just mistakes, and whether they were invented on Wikipedia or invented somewhere else.

> You shouldn't ever be citing sources who only claim to be communicating the work of others

With the exception of secondary research, like systematic reviews. Conclusions are good to have.