The problem is that because of their obvious bias, we can have no assurance that they are accurately surveying all of the available meta-analyses, and that they are properly representing the information and its level of certainty.

That is true, but one should still give it a read, instead of dismissing it as lies just because it was commissioned by a union.

Some pretty interesting stuff is included, from very interesting sources, pretty certainly not pro-worker biased.

And ultimately, if public-private partnerships, privatizations and the like were consistently good, it would be a struggle to find studies that do not corroborate this. Here we have a tonne of studies from various sources, none finding these fabled results.