

If by reliably you mean 99% certainty of one particular review, yeah I wouldn’t believe it either. 95% confidence interval of what proportion of a given page’s reviews are bots, now that’s plausible. If a human can tell if a review was botted you can certainly train a model to do so as well.
What do you mean by “this stuff?” Machine learning models are a fundamental part of spam prevention, have been for years. The concept is just flipping it around for use by the individual, not the platform.