As a computer science guy I did my own ELI5, found out how insertion sequences work, found the paper about HIV-1 and 2019-nCov, but it is true, it takes time to understand.

Even without spending time my heuristics is that I find biases in the claim and find out how referenced it is. This one had plenty red flags, including dismissing the RaTG13 results claiming that they were just put into the database after people started questioning, the adversarial tone, presumptions and so on. Conspiracy theorists use recognizable heuristics, but their motivation is to seek attention, for which there is large competition. They want to be relevant, but who doesn't. Conspiracy theorists are not really into publishing a paper either, a blog post, video or tweet is all you get, it's not about the truth and it is easier to avoid being found out this way, though social media these days have fact checkers, so they have to fly under the radar or keep to the social circles that are not bothered by fact checkers.

Knowing about biases and how to recognize them is a vital skill, should be taught in schools. Everyone needs a working bullshit meter.