This leaky bucket approach seems ineffective, ignores the root cause, and likely emboldens people adhering to these ideas. As bizarre as it sounds, I think the root cause for the rise in supply and demand for misinformation is the decline of the church/religion. Couple that with technology and it's uncharted territory. Many people need something to believe in, whether it's luck, god, nature, whatever, beliefs are complex frameworks that order a chaotic world. They help people handle a number of difficult circumstances from inequality and injustice to fear and uncertainty, to loss and sadness, to dealing with difficult people, finding motivation, the list goes on.
Like religion, conspiracy theories fill many of those voids, but they are much better equipped to thrive in the 21st century. Where churches build communities in buildings, conspiracy theories form communities on social media and internet forums. Where churches hold the carrot of an afterlife or ultimate application of fairness, the conspiracy theory holds the carrot of a future leak or whistleblower leading to your team's ultimate victory and subsequent righting of wrongs. Where church uses god as the reason for everything, conspiracy theories use mini-gods arising from issues, responsible for all sorts of machinations and plots. Where churches use imperfect human leaders capable of hypocrisy and moral shortcomings, conspiracy theories often lack formal leaders, and when they are present, the bar for morality is low compared to the alleged crimes of the conspirators. Churches ask for money, conspiracy theories ask for time. Churches offer boring lectures on people who lived thousands of years ago, conspiracy theories are engaging and tie directly to real world events.
Whack-a-mole with ideas that keep popping up does nothing to solve the underlying issues: there are many people out there who feel empty in some way and they are desperate to fill that void with just about anything. Containment of misinformation has failed and will continue to fail, just like prohibition of drugs fails, and abstinence only sex education fails, and religious persecution fails.
I think the best approach is to ignore, minimize, monitor real-world impact, and organically counter. With that approach you avoid creating martyrs, and you can exploit a major weakness conspiracy theories possess compared to formal religion: Conspiracy theories operate in the realm of the living, there is no promise of truth in death as with many religions. Because of this, very few conspiracy theories truly stand the test of time, eventually they're either disproven, evolve to become too outlandish, or simply become boring and fizzle out.