Technology

As much as I loathe that term, it could be argued that they indirectly are.

The massive increase in the amount of people online made it profitable for companies to be online. Lack of regulations and the inability for regulators to keep up with technological advancements allowed companies to maximize profits at the expense of everything else. The complete inability of government to prevent monetary influence on legislature has prevented good regulations from developing. The fact that the average person online uses maybe five websites in total and doesn't engage further means that most issues fly under the radar of the average person, which limits the ability of any significant amount of constituents to pressure the politicians supposedly representing them to do better, and limits the overall impact of any movement away from shitty sites to better ones.

It's a tangled yarn ball, but one that would struggle to exist without a majority of people to pull money from who just do not care about any of the shit that people more deeply invested in the internet care about.