Something having political implications does not inherently make it political. The timing of solar eclipses have had important political implications, that doesn’t mean their political in nature.

Aka, Union vs Non Union means different practices in aggregate and studying the results of those differences is valuable real world data.

Of course most things have a political element.

That doesn't mean they are political.

The study is about New York. The comment is trying to make this a 'red state vs blue state' thing. There's no reasonable basis for such thinking if you actually read the study.