How many products with seed oil also contain some form of added sugar? I don't seem to have much issue with moderating the occasional bag of cheezits or goldfish, but the moment I start getting into cookies and ice cream it's like a junkie broke into my house.
I am curious which is worse in terms of contribution to modern chronic metabolic disease.
In the case of ultra-processed/refined oils though, there is an argument to be made that these are novel foods that humans never ate until very recently. There aren't any old people who have been eating them their whole lives in the quantities we do now. This is probably true for industrially refined sugar too, but sugar is a more complex story since people have been concentrating plant sugars for a lot longer than they've been industrially refining oil for food.
I'm not defending sugar though to be clear - I strictly avoid it and even avoid fruit juice and such. I know empirically for myself I feel terrible if I eat very much sugar. I also feel terrible if I eat much refined oil and I strictly avoid that too.
The evidence against seed oils is not quite as convincing. I see seed oils as a low quality food to be avoided - goes rancid too easily, requires chemical processing, etc. - but it's not strictly poison. These oils are in virtually every industrial "food product" which makes them unhealthy by association. Stop eating highly processed crap and you'll see the benefits - cutting out seed oils is a side effect.
I don't have evidence for this specifically, but there's certainly a long and documented history of both a) influencers suddenly adopting a new party line in response to a paid campaign and b) shitty policy specifically for the influential corn industry (ethanol subsidies, e.g.)