I’m not a lawyer and won’t address the merits or lack thereof of the ruling on the particulars of the case. The effect of the ruling was a sweeping change in money in politics. It effectively legalized an oligarchic take over of governance. It’s a fact that money and advertising largely determine outcomes in battleground races. Tipping those races, along with the structural power imbalance in federal politics, means that control of the government is relatively easy and cheap.
https://rooseveltinstitute.org/publications/15-years-after-c...
I don't know if you read your own source but it's incredibly unconvincing "research" slop. In their "case study" they just point to a particular race and the money the candidates received and infer it's bad.
No analysis if the politician was acting against their constituents interests... Pretty embarrassing paper to put their name on. I can see why there's no coauthors.
Also they conflate political ad spending with issue awareness ad spending, which is a borderline malicious.