I am not credentialed in this area but have been reading studies closely for some years now. My take is that the major risk factor for arterial plaque is primarily systemic inflammation affecting the tight bonds between the epithelial cells in the tunica intima, followed by the number of small dense LDL particles, followed by HBP.
There seems to be little / no connection between serum SDLDL and dietary fat intake, but the connection between olive oil could be explained by a component ini EVOO which is highly anti-inflammatory (oleocalthal). Oleocanthal content in olive oil is highly variable, higher in early pick EVOO, less in other EVOOs, pretty much absent in lower grades of olive oil.
There's some evidence that inflammation affects the tight epithelial junctions in the gut as well.
Agreed 100% on toxicity of 'trans' fats, but they can occur in any unsaturated fat kept near its smoke point for an extended period (e.g. deep frying). I'd argue that the move away from saturated fats for that application was highly misguided. Just looking at how the oxidation process does this conversion suggests that monounsaturated fats (e.g. peanut oil) are less susceptible than poly, but I've seen no evidence, but if I ran a restaurant, thought my patrons would have issue with sat fat, I'd pick a mono (just thinking of MacDonalds' multiple fails in this area).