Nuts and seeds are known for their fat and protein content. Legumes are known for their protein content. Avocados are known for their fat.
all the things you're talking about involve pressing seeds.
This claim does not have any sense. If there is a thing that most plants are known for, is as a source of valuable products after being processed.
Some of the most appreciated vegetable oils, like olive oil or avocado oils, are not even in the seed.