The problem is that for any of what you're describing to work, AI has to be capable of comprehension and interpretation, neither of which are capabilities that LLMs have. This would be a quantum leap forward in terms of AI technology.

That's the key thing that has to be understood about "AI"; it fundamentally does not understand any of the words that it's saying. It's engaged in nothing more than extremely complex mimicry. Even a dog has more comprehension of human language than an LLM, and you wouldn't trust a dog to fact check political ads. Remember, even when working from accurate training data, LLMs will still cheerfully invent entirely fictitious data that just happens to fit the pattern of the training data, because that's all they are; pattern matchers.

If I present an AI with the statements "Mike Harris sold our LTC care system to corporate profiteers" and "Mike Harris sold your grandma's house to corporate profiteers" it has no way of accurately determining if the latter statement is true or false, because it fits the pattern of the first statement. A human can instantly distinguish between the concept of a long term care home and a person's privately owned house. An AI doesn't know what a person is, what a long term care home is, what ownership is, what the difference between private and public ownership are, what a house is and how that's different from a long term care home even though both are referred to as homes, what it means to sell something, what profiteering is and whether or not that term accurately describes the actions taken by the corporations that bought most of Ontario's LTC system. And then you have to get into the complex legalities of whether or not you're allowed to use the term "profiteers" in a political ad... It's a nightmare of complexity.

If there's a way to get to what you're describing, from where we are now, no one has come up with it yet and the first company that does will be rich beyond their wildest dreams. We're just not even remotely close to that kind of technology.