People fall for it because it’s so seductive.

They were fine with trans fats being bad, but when saturated fats are also demonstrated to impact health outcomes by the exact same methodology, they resist it because it condemns their favorite foods.

The current state of research does not provide strong evidence for a link between saturated fats and cardiovascular disease: https://pubmed.ncbi.nlm.nih.gov/20071648/

It seems the health benefits are contingent on what you replace saturated fat calories with (i.e. replacing saturated fats with polyunsaturated fats does seem to reduce heart disease, but replacing them with processed carbs does the opposite.)