It's likely due to the DEI-stock market angle that so readily spread the infestation in less than a decade. Corruption can wreak havoc so much faster and harder when someone waves "free" money in front of corporations who might be experiencing financial setbacks, and when said corporations are infested with investors who are actively buying into said trend.

Then expand those same incentives into government, and media, and you have yourself a full on cultural and economic takeover of multiple countries.