There's a lot of evidence that any fat and any cholesterol is worse than none at all. That means you just have to choose the lesser evil if you want to eat fat, and according to most big population studies that's just eating it raw from plants, like seeds and fruits. The main problem is getting the essential aminos other than ALA, those are found in seaweed or you need to supplement them.
The only essential fatty acids are linoleic and alpha-linolenic. It's virtually impossible to be deficient on anything like a normal diet. Oils/fats contain effectively no amino acids, essential or otherwise.
I would call both olive oil and coconut oil moderate sources of palmitic acid. It's present in greater proportion than in most other vegetable oils, but substantially less than in animal fats and palm oil.
Re: seaweed and supplements, you're thinking of DHA, which is non-essential but probably beneficial to consume in amounts greater than can be synthesized. Seaweeds however, containing very little fat overall, are not a very good source.
Very interesting video about this and more from What I've Learned: https://youtu.be/rQmqVVmMB3k
https://www.oliveoiltimes.com/world/frying-with-olive-oil/30...