Meat, I can't answer for, but I've been to a plant that processes fries for McDonald's, and they're just as real as they can be. The oil they're fried in? That's a different matter.
I don't know if there is a business reason to use the grease they do besides fear of the food Nazis, but food tastes better fried in animal fat.
No offense, but I’d have to see the real potatoes and the WHOLE process before I’d believe they were just cut, unprocessed potatoes.
I remember bringing up 100 lb bags of Idaho potatoes from the basement, abrading them and chuting them to the dual processing sinks, cutting them, washing them and then blanching them to be ready to final cook. That crap they have today is not the same - in no way. Oil or composition, it really doesn’t matter to me. They’re crap by the time you get them home.
BTW, back in the day, McD used fresh potatoes, which they peeled in a cylindrical device right in the building.