Postmodern sociology is revisionist towards trying to see society only through a lens that is also easily probable to be statistically sound, this is because of how more quantitative socioeconomic theories failed to predict very big crises or events in society. It can be argued that asking for scientific rigor in sociology to the same extent as in other human sciences raises the bar too much because to validate some theories the experiments are either impossible, prohibitively expensive, or so massive that they would bias the whole of society.

Also, I think it would marvel you knowing how much things you would call "scientific study" are also heavily politicized.

If this bothers you to a big extent I would recommend you try to find comfort in thinking about postmodern sociology as a religion different than yours. They won't be bothered by it and it will probably fit your mindset in a more soothing way than thinking about them as scientists. It's not that they are trying to publish their findings in ACM TOPLAS or something, they have their own community and books and kinda like it.