Our bodies actually like saturated fats. SFA is more energy dense and compact, and is what the body likes to store away for rainy days. We actually synthesise ingested fats so as to make them more saturated, and this takes energy to do, so the body prefers satfat since it can snip cut and paste to form whatever fat we need and then it is this cut+shut fat that goes into the lipids. so our fat is not the lard we just ate, but a personalised satfat or two made from it. even low fat eaters will have satfats in their blood, simply because our proteins need the more complex fats.
we make our cholesterol and we fill it with what we need simply because ingested foods are alien to our inner workings, and would get attacked by our immune system if not properly stamped with our own personal postcodes. But seed oils, if in abundance, does get into the lipids, and this is why seed oils sre inflammatory - they are not house trained since that takes time and energy to do, so they trigger a reaction wherever they go.
Having said all that, we need both Omega-3 and Omega-6 fats and it is better if they are matched . Modern processed foods are mainly omega-6 based, and this imbalance needs to be evened up a bit.
The advice seems to be for every 4 grams of Omega-6 you should eat 1 gram of Omega-3 (4:1 ratio) but ratios to 1:1 are reasonable
The modern diet is estimated to be between 50:1 and 100:1 mainly Omega-6