Seed oils are like canola, soy, "vegetable", sunflower, etc. They're the cheapest, so they're used wherever they can be

As for alternatives, some people say grass fed butter/ghi is the easy to go, personally I mostly use olive oil (although I'm not super clear on why that's different)

Ultimately, something is very wrong with our diets, and seed oils + sugar are where the experts offering explanations seem to be pointing. There's other things it could be, like micro plastics and the million other containments in our food and water allowed in doses that don't cause obvious harm, and even foods like tomatoes and potatoes that contain toxins (ones that are minimal if you prepare them properly, but we don't prepare them how we used to)

I definitely recommend researching it, and I'd be interested to hear what you come up with