This seems likely a garbage-y study. It's a narrative study, not even a meta-analysis, so it's more of proposing a hypothesis rather than stating a fact. The current science shows that seed oils, and omega 6 (aka linoleic acid) fatty acids, are either benign or healthy. There was a very popular hypothesis that the omega 6 to 3 ratio was important for health, popularized in the early 2000's and getting revived now by counter-culture nonsense people, but the science has not backed that case up.

They study they link to citing neuro-development issues is https://pubmed.ncbi.nlm.nih.gov/28420388/ - which is based on a food intake survey, and it's not a controlled study, it's looking at cohorts from another study. All they checked for was linoleic acid intake, and unless you're specifically checking for food source, this usually means it comes from processed food, which is more likely the culprit than the 6 to 3 fatty acid ratio.

There is no known effect of seed oil / omega 6 intake on inflammation, which is shown in quite a few controlled studies. Seed oil intake replacing saturated fat intake has also been shown to significantly reduce CVD outcomes.