Barry Keoghan was so miscast. Oliver was obviously meant to be charming and cute in the script
There is no way anyone would be charmed by Barry Keoghan. And he didn't even try to be nice and cute. His Oliver is creep and psycho.
There was no reason for Felix to single him out and wanting to hang out with him. He wasn't fun. Or smart. He was looking like depressing sad ugly psycho.
Then he shows up at mansion and again - all those rich people fall in love with him at a moment. While he literally is just walking around looking ugly and quiet. He wasn't sexy and anything either.
Yet all those people fell at his knees. He is basically male version of Mary Sue.
Movie had to be realistic. They had to hire cute or at least charismatic actor to play Oliver. Because it's obvious he was that way written in script. This role required someone looking like young Jude Law, young Ryan Phillipe, young Ethan Hawke. That type of hot sleazy bastard.
And it was actually very bad acting from Barry Keoghan. As he is not a good actor. He didn't even try to look nice and charming. He had one face expression throughout whole movie. For some reason Hollywood tries to make him happen. He will not Happen. That's why Saltburn flopped at the box-office. People dont care to see Barry Keoghan in lead role. No matter how Hollywood press and studio try to hype this movie at awards season.