it's actually true. they cause serious inflammation which aggravates serious downstream health problems. like, you shouldn't be eating seed oils in any large quantity that you would get from regularly eating deep fried foods
oh but wait, eating foods with beef tallow and other saturated fats also causes health problems. except, those problems only show up when you eat large quantities of them, such as if you were regularly eating deep fried foods
so what if it wasn't the seed oils that were the problem for many people, but rather, consuming lots of seed oil - as you might find if you ate a lot of deep fried food?
what if it's not the seed oils that are causing you to get fat and feel like shit all the time? what if it's the quantity of fats that you're consuming? and, what if not eating seed oils is actually an easy an effective way to avoid eating deep fried foods as a second order effect?
that'd be crazy. better just jump on the new fad diet.